Not sure how the ABS sensors look on this car but on others there is a toothed metal "cage" that gets pressed over the hub. This cage creates a hall-effect eddy current in a fixed electromagnetic near the cage's perimeter.

These cages are easily damaged when removing the hub for wheel-bearing work (and other types of ABS rings can get damaged by small stones, etc). If a cage loses a "tooth" it can make the wheel appear to stop at low speeds when it has not actually done so.

My first guess would be to inspect every single tooth at both front wheels. If those check out, move to the back, where you might have two sensors or a single rear sensor in the differential that's unlikely to get damaged.

Good luck and happy new year.

Ted

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1983 240D automatic, Orient Red, 174K
1983 240D manual, Biscayne Blue, sold at 341K