The transformations in Gear Krieg are relatively minimal- more like extending the drive train to a different mode than completely changing the shape and role of the vehicle the way transformers or Robotech veritechs do. The kubelwagen on legs by the OP would fit right in with GK models. I find the rationales for transforming war machines (or walkers) a bit thin, usually, but within that genre Dream Pod 9’s Gear Krieg (and Heavy Gear for far future sci-fi) are relatively plausible, in my opinion. The vehicles are a reasonable size with fairly specific tactical roles and the transformations or walker locomotion is mainly for boosting mobility in specific circumstances. They break laws of physics relatively rarely…