How to set git-lfs as an additional checkout behavior using the JCAC plugin?
It seems that it is only possible by using a workaround as depicted in this answer.

After setting gitLFS in the UI, subsequently inspecting the /var/lib/jenkins/jobs/some-job/config.xml file it became obvious that the XML looked as follows:

&lt;traits&gt;
   &lt;jenkins.plugins.git.traits.GitLFSPullTrait&gt;
      &lt;extension class="hudson.plugins.git.extensions.impl.GitLFSPull"/&gt;
   &lt;/jenkins.plugins.git.traits.GitLFSPullTrait&gt;
&lt;/traits


After defining jenkins.plugins.git.traits.GitLFSPullTrait:

jobs:
  - script: &gt;
      multibranchPipelineJob("example") {
        branchSources {
          ...
        }
        configure { node -&gt;
          node / sources / data / 'jenkins.branch.BranchSource' / source / traits {
            'jenkins.plugins.git.traits.GitLFSPullTrait'()
          }
        }
      }


Git-lfs was enabled.