Sabine is not a Mary Sue
Jyn Erso was not a Mary Sue
Hera is not a Mary Sue
Ahsoka was not a Mary sue.
Rey... totally was. Though nowhere near as much as say Alice from the Resident Evil movies, Tom Paris from Star Trek Voyager, or if we're looking at other Star Wars stuff, Starkiller from the Force Unleashed games is probably the most blatant example..
No. Just no. I've rarely seen a movie go through as much pain as TFA did to establish pretty much every one of her abilities, which I will note neither ANH or TPM remotely did for Luke/Anakin.
Even if you don't want to count novels, being a scavenger of tech, most of it starships, required her to learn a TON of about them. How they work, how to repair (the better the part works, the greater the portions), and yes, how to fly them because again, the more you know about all these ships, the less time you waste salvaging junk that doesn't get you paid. And heck, the fanciest thing she does with the Falcon is the fly through the Star Destroyer wreck, which again, she knows that damn SD. She's likely been in it hundreds of times.
Languages? Again, scavenger on a world of refugees and castoffs. The more you can understand what people are saying, the better for you. Less likely to get scammed, can pick up info from people who think you don't understand them, might be able to make a trade with an offworlder for something the Blobfish isn't going to give up.
Fighting? They have the scene with the thugs for a reason. You learn how to fight off other people or You. Don't. Eat. And mind you, she spends 90% of the fight with Ren on the defensive barely getting a hit in, so it's not like she magically dominated the fight. And the movie again went to great lengths to show just how powerful Chewie's bowcaster was, so we'd know just how bad a hit Ren took, which knocked his skills down. Not that he's that skilled - he's raw power throwing tantrums for the most part.
The biggest issue is the mind trick, which heck, SHE was shocked worked, and that's also stupid Ren's fault for thinking no one could turn his mind probe back on him. He should know better if his uncle ever taught him anything. SW characters find out they can use the Force and suddenly get power ups. Luke goes from "Hey I'm a pretty good pilot!" to making an impossible shot his first time flying in a vacuum. Anakin goes from "only human not killed in a pod race" to winning one, and taking out the Trade Federation Fleet. Heck even Leia goes from "I don't have that power" to knowing with complete confidence that her brother is alive because SHE CAN FEEL HIM.
Sorry, I've just spent too many years reading stories with ACTUAL Mary Sues to deal with this nonsense. Especially when the male characters don't need so many levels of justification for why they are good at anything.
ANYWAY. Sabine Suite on loop. Awwww yeah.