Question on four-wheel and tire wear

Moin, today I cleaned the car a little bit, checked tyre pressure and measured profile. The front tyres are so at 5mm both. The rear tyres were always a bit better during previous checks and had pi times thumbs a millimeter more profile on it. Now the rear left tyre has still so 6-7mm, the right rear one suddenly reaches only 5mm. In the past there were no measurable deviations between left and right. Since I have not driven so much lately, w I already change myself about the suddenly strong wear of a tire. Since this problem did not exist before and I do not drive any curbs up and down and even nowhere with the tire or the rim I exclude a suddenly adjusted track first rather. The car also runs normally straight while driving and braking. However, I have the feeling (maybe it is really just a feeling) that the wheels erase something when I slowly drive a narrow left turn. So, al Is it not always the case, especially right after the start, when everything is still cold. How best to do it? Can you somehow check whether the drive train is tense or just feeling? I would not like to have new tires put on it soon, as long as the problem is not found. If it’s stupid, I’ll ruin a tire again. It’s a Subaru Forester with automatic, because it’s a Subaru Forester. s means that the all-wheel is permanent (normal power distribution probably at 80:20)m if required up to 50:50 and is controlled by a lamella coupling.