Mileena controls where KJ controls but better. B12 breaks armor. I have to use armor to get out of the staggers. Have to.
How well do you do against those Mileena because if you are going even then you gotta teach me. She has a tool for every situation.
I wouldn't say I go even with foxy but I do pretty well if I'm honest (considering who it is and all lol). When I lose I feel it's because it's foxy, not because Mileena. The reason I think it's fine is because of how she has to use low Sai full screen because of low chakram low profiling and on trade Jin actually wins (7% vs 6%). When she uses low sai it also puts her at massive risk. You can punish on reaction from CRAZY range with ex divekick. I would recommend labbing it to see for yourself.
Then that brings in her teleport. If you want to beat mileena players you have to get used to punishing the teleport or teleport xx air sai consistently. Personally I d1 aa her when she air sais then convert, and when she just lands without sai I punish with 221. I still mess this up but it is very possible to consistently punish. The reason I say this is important is Mileena's will try and teleport on chakram (which is pretty easy considering its recovery) and so when you bait it you need to punish.
B12 does break Carthweel which sucks but it won't break it at -1 (after b12). This makes it a good option to reversal with especially as it will actually punish her trying to do a d3 check afterwards. It's also hard to make whiff so is a very safe option. F1 is really annoying to deal with seeing as it will blow up all armors and is +2 on the stagger. If you are able to react quickly to the stagger then you can blow up everything but a poke or s2 by using 221. I'm not good at reacting to it but that is where I know I can improve.
As for her b12 in the neutral, Jin actually has a better time whiff punishing it then a lot of others. b1 and b2 being his best options for the whiff punish and divekick if already in the air obviously. Not saying whiff punishing b12 is easy, it is aids lol. b1 on it's own is not going to be whiff punished in my opinion either. I normally ABUSE 11 with Jin in the neutral but I find it near useless in this MU so I rarely use it.
One thing she does really well in the MU is deals with upkick on block. You kind of have to hold her b1 after the drop or even the empty drop (as long as they are on point reacting to it) and you can't armor with cartwheel (or upkick) because b12 will break and they can convert off you being airborne very easily. You can use ex bf3 though the reward for hitting this is very low. That being said, because they know you can't cartwheel they very rarely bait the ex bf3 in my experience. Backdashing is simply not an option from what I've looked at either, because his backdash is not great and b1 easily catches it. You can't jump either because guess what... b1 catches you (although if she does b12 the second hit will whiff and so you don't get punished badly). I actually realized that when I was doing this I had to be very on point to catch the jump forward with b1 so you can go for it and they hope they mess up because then you get a free divekick whiff punish. Anyway this is a weakpoint in the MU for me as you end up eating a lot of reversal throws after upkick because they know you have to hold b12.
I guess the last thing is oki. Jin does just fine here, as he can quite easily break ex ball with 221 and convert so they have to be respectful of that. D3 check is also completely safe on ex ballroll (though after d3 on block she has the 6f d1 now so getting anything at +1 isn't guaranteed with Jin). A thing I like a lot about the MU is her d1 has awful range so you can bait it after things like s1 on block and punish with walk back b1. It is actually possible to walk back and make the d1 whiff after blocked d3 at further ranges which makes the d3 check better.
EDIT: I forgot to talk about her absolute aids jump1. d1 and s2 aa are absolutely useless against this abomination of a jump attack. If she does the crossover properly then it will hit you before you have even autocorrected so you can't aa that on reaction at all. However if it is just a standard crossover s1 aa is his best option in my experience. The only time d1 is good in this MU is on long range jump ins as it also beats jump kicks, though mileena players should never need to rely on random jump ins. I personally don't mind spending the bar on ex cartwheel for the safe aa vs j1.
Sorry for massively long post lmao, I just sort of had a lot to say haha. Let me know if you disagree on anything though.