Sounds like you want Injustice, since it’s the most similar to MK9 and incredibly easy to learn. For many characters, you’ll be able to do all of their best stuff within hours, even as a beginner. The only problem is that the netcode is pretty bad.
Persona 4 Arena is a fairly good beginner game on the anime side. Half of the characters are easy to play, and the game has amazing netcode, but it’s like night and day from MK9/Injustice.
UMvC3 IMO is fairly hard to get into just because it will take you a long time to recognize what is happening and learn all of the matchups, and you might get frustrated with not understanding why you’re losing. Wavedashing and plink-dashing will also probably be difficult for a beginner on pad. If you favor heavy teams, you can cut out some of the learning curve.
Edit: Skullgirls is actually a really good recommendation if you like Marvel, since it’s inspired by MvC2 but has a lot less clutter on the screen, and fewer characters to learn. The netcode is also superb.