I would bet we'll see Sebastian Stan as Luke Skywalker
now , that doesn't mean I'd bet the farm on it , but I'd be willing to bet a couple bucks on it
maybe they don't want to use Luke Skywalker at all , and this will all be but a mute point
but if they do want to use Luke Skywalker , then it comes down to how much and how big of a part
if it's just a one off 20 second cameo , then use Mark Hamill with the deaging thing
but if they want a bigger part , with a young Luke Skywalker in all his Jedi glory , then they need to use Sebastian Stan
both Sebastian Stan and Mark Hamill seem to be both for it
Sebastian Stan already works for Marvel/Disney anyways , so to have him pop over to the Star Wars set for a couple days , probably wouldn't take much effort at all
one thing Jon Favreau and Dave Filoni seem to be getting right with The Madolorian is that they've obviously have been listening to Star Wars fans
so , I do expect to see Sebastian Stan as Luke Skywalker at some point , maybe not this season , but some time down the line