Many years ago (before I started using it, apparently), it was called youtube-creator-studio, but it's since been rebranded to youtube-studio. The former should therefore be a synonym of the latter. If we really want to be thorough, studio.youtube.com (the URL) would be another good synonym.
I wonder if it might be better to make youtube-creator-studio a synonym of youtube. The first, was created almost 6 years ago, it only has 20 questions, 35% are unanswered, and all are tagged youtube, nobody has got a score of 100 and has posted 20 answers, required to earn the tag bronze badge.
Yesterday, I approved an edit suggestion for the youtube-creator-studio. It looks to me that the tag wiki still needs work.
It's worth noting that nowadays, Stack Exchange has Video Production. From their tour
Video Production Stack Exchange is a question and answer site for videographers, producers, editors, and enthusiasts spanning the fields of video, and media creation. It's built and run by you as part of the Stack Exchange network of Q&A sites. With your help, we're working together to build a library of detailed answers to every question about video recording and production.
Their youtube tag has 229 questions. They don't have a specific tag for YouTube Studio.