You can create a picture library in a communication site using the PnP provisioning template.

Below is the xml template to create a picture library named Banners. You can substitute banners with the name of the picture library you want to create.

<?xml version="1.0"?>
<pnp:Provisioning xmlns:pnp="http://schemas.dev.office.com/PnP/2020/02/ProvisioningSchema">
  <pnp:Preferences Generator="OfficeDevPnP.Core, Version=3.22.2006.2, Culture=neutral, PublicKeyToken=5e633289e95c321a" />
  <pnp:Templates ID="CONTAINER-TEMPLATE-44CFD9C6658C47D89595FA4F33D054FF">
    <pnp:ProvisioningTemplate ID="TEMPLATE-44CFD9C6658C47D89595FA4F33D054FF" Version="1" BaseSiteTemplate="STS#0" Scope="RootSite">
      <pnp:Lists>
        <pnp:ListInstance Title="Banners" Description="" DocumentTemplate="" TemplateType="109" Url="Banners" MinorVersionLimit="0" MaxVersionLimit="0" DraftVersionVisibility="0" TemplateFeatureID="00bfea71-52d4-45b3-b544-b1c71b620109" ContentTypesEnabled="true" EnableAttachments="false" DefaultDisplayFormUrl="{site}/Banners/Forms/DispForm.aspx" DefaultEditFormUrl="{site}/Banners/Forms/EditForm.aspx" DefaultNewFormUrl="{site}/Banners/Forms/Upload.aspx" ImageUrl="/_layouts/15/images/itil.png?rev=47" IrmExpire="false" IrmReject="false" IsApplicationList="false" ValidationFormula="" ValidationMessage="">
          <pnp:PropertyBagEntries>
            <pnp:PropertyBagEntry Key="IsAttachmentLibrary" Value="0" Overwrite="false" />
          </pnp:PropertyBagEntries>
          <pnp:ContentTypeBindings>
            <pnp:ContentTypeBinding ContentTypeID="0x010102" Default="true" />
            <pnp:ContentTypeBinding ContentTypeID="0x0120" />
          </pnp:ContentTypeBindings>
          <pnp:Views>
            <View Name="{7F793C3D-F302-4F87-AAB2-EC76A8DD0E9B}" MobileView="TRUE" MobileDefaultView="TRUE" Type="HTML" DisplayName="All Pictures" Url="{site}/Banners/Forms/AllItems.aspx" Level="1" BaseViewID="1" ContentTypeID="0x" ImageUrl="/_layouts/15/images/plicon.png?rev=47">
              <Query>
                <OrderBy>
                  <FieldRef Name="FileLeafRef" />
                </OrderBy>
              </Query>
              <ViewFields>
                <FieldRef Name="DocIcon" />
                <FieldRef Name="LinkFilename" />
                <FieldRef Name="ImageSize" />
                <FieldRef Name="FileSizeDisplay" />
                <FieldRef Name="Modified" />
                <FieldRef Name="RequiredField" Explicit="TRUE" />
                <FieldRef Name="PreviewOnForm" Explicit="TRUE" />
              </ViewFields>
              <RowLimit Paged="TRUE">40</RowLimit>
              <JSLink>clienttemplates.js|callout.js</JSLink>
            </View>
            <View Name="{4407A5B5-DF75-4377-8955-1CADB6F626AF}" DefaultView="TRUE" Type="HTML" DisplayName="Thumbnails" Url="{site}/Banners/Forms/Thumbnails.aspx" Level="1" BaseViewID="6" ContentTypeID="0x" ImageUrl="/_layouts/15/images/plicon.png?rev=47">
              <Query>
                <OrderBy>
                  <FieldRef Name="FileLeafRef" />
                </OrderBy>
              </Query>
              <ViewFields>
                <FieldRef Name="DocIcon" />
                <FieldRef Name="LinkFilenameNoMenu" />
                <FieldRef Name="ImageSize" />
                <FieldRef Name="FileSizeDisplay" />
                <FieldRef Name="Modified" />
                <FieldRef Name="Created_x0020_Date" Explicit="TRUE" />
                <FieldRef Name="Author" Explicit="TRUE" />
                <FieldRef Name="Editor" Explicit="TRUE" />
                <FieldRef Name="RequiredField" Explicit="TRUE" />
                <FieldRef Name="ImageWidth" Explicit="TRUE" />
                <FieldRef Name="ImageHeight" Explicit="TRUE" />
                <FieldRef Name="NameOrTitle" Explicit="TRUE" />
                <FieldRef Name="PreviewOnForm" Explicit="TRUE" />
                <FieldRef Name="StartDate" />
                <FieldRef Name="EndDate" />
                <FieldRef Name="ShowAsPopup" />
                <FieldRef Name="Category" />
              </ViewFields>
              <RowLimit Paged="TRUE">30</RowLimit>
              <JSLink>SP.UI.TileView.js|callout.js</JSLink>
            </View>
            <View Name="{B48B63E2-F54B-485C-99D2-37D6B06A87BD}" Type="HTML" TabularView="FALSE" DisplayName="Slides" Url="{site}/Banners/Forms/SinglePict.aspx" Level="1" BaseViewID="2" ContentTypeID="0x" ImageUrl="/_layouts/15/images/plicon.png?rev=47">
              <Query>
                <OrderBy>
                  <FieldRef Name="FileLeafRef" />
                </OrderBy>
              </Query>
              <ViewFields>
                <FieldRef Name="LinkFilenameNoMenu" />
                <FieldRef Name="FileSizeDisplay" />
                <FieldRef Name="ImageSize" />
                <FieldRef Name="NameOrTitle" Explicit="TRUE" />
              </ViewFields>
              <RowLimit Paged="TRUE">1</RowLimit>
              <JSLink>clienttemplates.js</JSLink>
            </View>
          </pnp:Views>
          <pnp:Fields>
            <Field ID="{d1cff744-ba61-4189-94d6-97d0a9eb4f6a}" Type="Text" DisplayName="Tags" Name="MediaServiceAutoTags" Group="_Hidden" Hidden="FALSE" Sealed="TRUE" ReadOnly="TRUE" ShowInNewForm="FALSE" ShowInDisplayForm="FALSE" ShowInEditForm="FALSE" ShowInListSettings="FALSE" Viewable="FALSE" Json="FALSE" SourceID="{{listid:Banners}}" StaticName="MediaServiceAutoTags" ColName="nvarchar11" RowOrdinal="0" />
            <Field ID="{67aff0cf-8e19-43f2-9987-be89075e1467}" Type="Note" DisplayName="Extracted Text" Name="MediaServiceOCR" Group="_Hidden" Hidden="FALSE" Sealed="TRUE" ReadOnly="TRUE" ShowInNewForm="FALSE" ShowInDisplayForm="FALSE" ShowInEditForm="FALSE" ShowInListSettings="FALSE" Viewable="FALSE" Json="FALSE" SourceID="{{listid:Banners}}" StaticName="MediaServiceOCR" ColName="ntext6" RowOrdinal="0" />
            <Field Type="DateTime" DisplayName="StartDate" Required="TRUE" EnforceUniqueValues="FALSE" Indexed="FALSE" Format="DateOnly" FriendlyDisplayFormat="Disabled" ID="{eecaae15-69aa-4d78-a2bf-63e8dfae43bf}" SourceID="{{listid:Banners}}" StaticName="StartDate" Name="StartDate" ColName="datetime2" RowOrdinal="0" />
            <Field Type="DateTime" DisplayName="EndDate" Required="TRUE" EnforceUniqueValues="FALSE" Indexed="FALSE" Format="DateOnly" FriendlyDisplayFormat="Disabled" ID="{67d10351-4820-4268-91c7-bbb398a1b7bb}" SourceID="{{listid:Banners}}" StaticName="EndDate" Name="EndDate" ColName="datetime3" RowOrdinal="0" />
            <Field Type="Boolean" DisplayName="ShowAsPopup" EnforceUniqueValues="FALSE" Indexed="FALSE" ID="{63bd5c44-fd9a-4ac0-b77f-f74817275b0b}" SourceID="{{listid:Banners}}" StaticName="ShowAsPopup" Name="ShowAsPopup" ColName="bit3" RowOrdinal="0">
              <Default>0</Default>
            </Field>
            <Field Type="Choice" DisplayName="Category" Required="TRUE" EnforceUniqueValues="FALSE" Indexed="FALSE" Format="Dropdown" FillInChoice="FALSE" ID="{4e8b55ae-a3f5-4bad-9110-61a9694f39cc}" SourceID="{{listid:Banners}}" StaticName="Category" Name="Category" ColName="nvarchar14" RowOrdinal="0">
              <Default>Slide Banner</Default>
              <CHOICES>
                <CHOICE>Slide Banner</CHOICE>
                <CHOICE>Product</CHOICE>
              </CHOICES>
            </Field>
          </pnp:Fields>
          <pnp:FieldRefs>
            <pnp:FieldRef ID="8c0d0aac-9b76-4951-927a-2490abe13c0b" Name="PreviewOnForm" DisplayName="Preview" />
            <pnp:FieldRef ID="c53a03f3-f930-4ef2-b166-e0f2210c13c0" Name="FileType" DisplayName="File Type" />
            <pnp:FieldRef ID="922551b8-c7e0-46a6-b7e3-3cf02917f68a" Name="ImageSize" DisplayName="Picture Size" />
            <pnp:FieldRef ID="7e68a0f9-af76-404c-9613-6f82bc6dc28c" Name="ImageWidth" DisplayName="Picture Width" />
            <pnp:FieldRef ID="1944c034-d61b-42af-aa84-647f2e74ca70" Name="ImageHeight" DisplayName="Picture Height" />
            <pnp:FieldRef ID="a5d2f824-bc53-422e-87fd-765939d863a5" Name="ImageCreateDate" DisplayName="Date Picture Taken" />
            <pnp:FieldRef ID="9da97a8a-1da5-4a77-98d3-4bc10456e700" Name="Description" DisplayName="Description" />
            <pnp:FieldRef ID="b66e9b50-a28e-469b-b1a0-af0e45486874" Name="Keywords" DisplayName="Keywords" />
            <pnp:FieldRef ID="7ebf72ca-a307-4c18-9e5b-9d89e1dae74f" Name="SelectedFlag" DisplayName="Selection Checkbox" />
            <pnp:FieldRef ID="76d1cc87-56de-432c-8a2a-16e5ba5331b3" Name="NameOrTitle" DisplayName="Name" />
            <pnp:FieldRef ID="de1baa4b-2117-473b-aa0c-4d824034142d" Name="RequiredField" DisplayName="Required Field" />
            <pnp:FieldRef ID="ac7bb138-02dc-40eb-b07a-84c15575b6e9" Name="Thumbnail" DisplayName="Thumbnail" />
          </pnp:FieldRefs>
        </pnp:ListInstance>
      </pnp:Lists>
    </pnp:ProvisioningTemplate>
  </pnp:Templates>
</pnp:Provisioning>

Save the template somewhere and run the following PowerShell script.

# using username & password
$userName = "yourusername"
$passWord = "yourpassword"
$encPassWord = Convertto-Securestring -String $passWord -AsPlainText -Force
$cred = new-object -typename System.Management.Automation.PSCredential -argumentlist $userName, $encPassWord
Connect-PnPOnline -Url "https://tenant.sharepoint.com/sites/yoursite" -Credentials $cred
 
# When multifactor auth is in place
Connect-PnPOnline -Url "https://tenant.sharepoint.com/sites/yoursite" -UseWebLogin
 
Apply-PnPProvisioningTemplate -Path "template.xml"