You're talking about the change from The Super Mario Bros. Super Show to Club Mario, which I vaguely remember. But all that was was replacing the live action with that new stuff while keeping the same cartoons. I don't think any original cartoon episodes were made under that banner. And then the next season, they returned with The Adventures of Super Mario Bros. 3 (my favorite series but one that I have a sad lack of episodes in my collection) with no live-action parts and Lou Albano and Danny Wells being replaced by Walker Boone and Tony Rosato as the voices of Mario and Luigi, a casting change that continued in the last season of the show, Super Mario World.