who do i gotta fight to get polaris introduced in the mcu
Pretty much both Marvel and Fox.
I’ve heard claims that Fox is being difficult with Disney and Marvel with the film rights, which I can see being potentially true since Disney and Marvel are able to strike deals with Sony about Spider-Man.
However, far more importantly, Disney and Marvel are doing things they think will somehow magically hurt Fox, but in actuality only hurts Marvel and makes them look worse than Fox. They’re doing a lot to undermine franchises that Fox owns the film rights for, and especially trying to ruin the X-Men franchise in the comics. Every crossover event, and even a lot of what happens in the Avengers books outside those events, is geared toward making the X-Men franchise look worse and shift its good elements over to the Avengers while putting the Avengers on a pedestal.
Most recently, we saw this with the forced retcon of Wanda and Pietro out of being Magneto’s kids in the comics themselves. There’s a lot more I could list at length about Marvel trying to undermine the X-Men and Fantastic Four, but that’s the best example.
Secondly, even if a deal was struck between Fox and Marvel, Marvel would then need to be pushed to acknowledge Polaris is an actual character that’s been around since 1968 and has a wealth of untapped potential that needs exploring. The company constantly excludes her from crossover events and never promotes anything she’s on (e.g. her origin story told in X-Factor #243 after 40 years without one, her first time hanging out with her sister Wanda in 10 years in All-New X-Factor #14, All-New X-Factor in general, etc). This is in addition to certain people on the Avengers comics side making subtle negative comments about her worth as a character and having key events she was part of redrawn during flashbacks to exclude her a few years back.
In all likelihood, we won’t see Lorna in the MCU until 10-20 years from now when a new generation takes over. That new generation will be more likely to see how stupid Disney and Marvel’s current tactic is in dealing with Fox owning the X-Men film rights, and will also be more likely to actually look at characters like Polaris and want to use her potential.
It also doesn’t help at all that Disney is trapped in the idiotic mental model of “our Disney princesses are for girls, so Marvel is for boys.” There’s been a lot of discussion lately about how the Marvel films and merchandise fail to represent women, especially focused on lack of representation for Black Widow. It’s ranged lately from how characters that aren’t even in the films have more toys than Black Widow when she’s in those films, how Renner and Evans calling Black Widow a slut in an interview is a result of the films setting Black Widow up to be the “token superheroine” in a sea of guys, etc.
Fox may be acting difficult with Marvel, but Marvel still has a lot of problems on their end to fix too before we have a shot of seeing Lorna in the MCU. We have a better chance right now of Fox introducing her to the X-Men films than of Marvel adding her to the MCU even if a deal was struck; Marvel currently doesn’t have enough respect for her.
salarta 
