Thank you for the support.
Try adjusting your foot spacing and the angle your feet are at
I’ve been trying this, and I found an area where I can squat without any pain or having that “butt wink”
The abductor/adductor machines are good for those muscle groups
I only have access to a barbell and dumbbells, but I have a ton of bands, I will figure it out, somehow 
Can you tell me where I can find the “stretches for your hip flexors, glutes, and outside/inside muscles and ligaments” I’m pretty bat at it tbh
Do you have pain in those areas after your leg days? Have you found anything that helps/makes it worse?
If I do the upward of the squat fast, I feel that pain for 2 or 3 days, It isn’t soreness, it is something on my ligaments or joints, I can’t explain and the doctors didn’t found nothing weird there.
The only way that I find to make it pass is resting and do some light movements, like walking and stretching.
About 5x5 being hard. I had trained for a entire year using lower weights with super slow tempo reps in order to “build muscle”, I was in a commercial gym full of big body builders and found some love by the strength recently. I was recommended to start slow and add 1kg in each side of the bar each train until I can’t and them ask for help again. I found a point where it got hard in some exercices, like Bent over Row, Bench Press, OHP, but for leg exercises I’m still finding it super easy in the weight aspect. My DeadLift is super easy and I never found a single problem with it.
And there is one thing that makes it worse, very worse, Jumping. Trying to do high jumps make it pretty bad.