Replaced the sensors now and cleaned out the cogs, they were clogged with a lot of black goo...
Still no difference it's like the car has decided that the ABS/TC are dead and isn't even checking it anymore.
Tried to remove the battery over night but didn't seem to change anything except time/date on the dash.
Just some history on how it started and why I don't want to believe it's the ECU:
Started with ABS/TC lights coming on as usual and when starting the engine they turned off after a few seconds.
If I drove in a straight line for the first 10 meters after starting the car I would heard a small metallic noise, like cogs clicking into place and the ABS/TC light went on and off again and worked fine until the next run with the car ( both ABS and TC worked fine during the run as well ).
But if I turned sharply right away, like coming out of a parking lot, it would disable ABS/TC and lights would turn on.
Few months later it just died and I stopped hearing that metallic cog noise and the lights have been on since then

The sound itself came from the back of the car, so I figured that the only mechanical feature would be ABS sensors + the cogs, or am I wrong?
Tried to find some similiar issues from other people but it's usually the ECU and the speedo/RPM dying at the same time.
Tried to find some local chaps but out here but it seems like the only option is to leave the car at an Opel dealer.
They
guesstimated 30-350€ for troubleshooting alone and repairs were anything from 20€ to 1500€, I don't have a lot of confidence in them after that discussion.
Would appreciate any suggestions here or should I just go for an ECU repair right away?