We have testing of renameCollection in our fsm workloads which run in stepdown suites (such as random_ddl_operations.js and its children). However, this only runs renameCollection within a database.

Looking at the tests we do have which exercise the rename across database path (like rename_collection_different_dbs.js in the core suites or rename_collection_dbname_droptarget.js in concurrency), these tests do not run in sharding stepdown suites.