My favourite Mary/Maria variants tend to be diminutives! Also, this is just using BehindTheName, sorry if any of it is wrong. I’m certainly no expert!
Manon -
Beautiful, sleek, and stylish. I had a major name crush on Manon at one point, and I still do love it. A French variation.
Mariska -
This is actually pronounced sort of like Marishka, and I love it! It’s mysterious, gorgeous,
Mitzi -
diminutive of Maria. Just so fun! I love it’s spiky sound.
Maricela -
how gorgeous is Maricela? 
It’s pretty, lively, and reminds me of a golden sun!
Mieke -
another diminutive, but I love how youthful and vibrant it feels.
Marisha -
I’m pretty sure this is a variant of Mary? It has its roots as a Russian diminutive of Marina, but also as a name in Hindu mythology. From what I can find it may have derived from ‘Maris’. One of my favourites!
There’s so many variants! Some others I like: Marianne, Maja, Mia, Malle