MigrateBatchExecutable has several @param references to \DrushBatchContext which was removed in Drush 13.
Phpstan now throws errors for code which extends MigrateBatchExecutable and uses any of the methods which accept \DrushBatchContext as a param.
Params should probably be updated in a new major release of Migrate Tools.
Active
6.0
Code
In the meantime, perhaps it should not declare compatibility with Drush 13.
I've been using the module w/ Drush 13 without issue, so I'm not sure what parts of drush 13 are broken.