Hi Richard!
I lifted the front end to compare both sides and they were sadly strictly identical. No leaks either. So I looked for a shop with high ratings and brought them the car. They put it on a lift, inspected it: nothing (well, 2 clips missing on the belly pan). They then took both left wheels off and put them on a wheel balancer. They added a small weight to one and that was it. The wheels weren’t bent or cracked. All of that took an hour and was very inconclusive so the mechanic took the keys and we went for a drive.
It took a couple turns for him to blame the front left wheel bearing, and notice the alignment was off and pointed the wheels to the right ever so slightly (to quote him, 1°).
Tomorrow the front left wheel bearing is getting replaced, after what if the issue is fixed I’ll get an alignment. If it’s not fixed, well…let’s not think about it 🙂
Again thank you for the advices, I’ll keep the thread updated if someone ever finds it.