Just watching you, without considering potential mobility restrictions, a huge part of the problem is most likely motor control. You mentioned you weren’t really aware you were squatting far off to one side until it was pointed out to you. It’s likely that you’re just favouring one side in your execution. Yes, there is probably some mobility restriction. Yes, there is probably some degree of strength imbalance side to side. But did these things cause you to squat crooked, or do you have those restrictions and weaknesses because you’ve been squatting crooked without knowing it?

My advice, before you dig down into the mobility rabbit hole, is to either squat with a mirror in front of you, or have someone coach you as you squat. Even something as simple as having a friend tell you rep-to-rep if you’re veering off in that favoured direction will be very helpful. If, in spite of being made aware of the asymmetry, you can’t get moving in the other direction, or doing so is unduly difficult, then concern yourself with tissue impairments (like mobility problems or strength imbalances) that might be contributing.

You’ll probably be able to sort this fairly easily with a little feedback.