I was gonna comment on this since I'm pretty sure they were outsourced, but I'm not sure how much Sega had a say on it. We do have a
design doc for SOR1 (in English at that) which definitely seems to come from Sega — interesting to read too, as it talks about what they may need to do to reduce memory usage as well as claiming that Final Fight's perspective is horrendous (characters always facing sideways when walking, unlike e.g. Golden Axe where they may face front or back depending on the direction they're moving), as well as the obvious stuff like character stats and the original plot and the like. On the other hand the
SOR2 design stuff we have seems to come from Ancient… I have no clue.
There has been definitely a big deal in recent times about how SOR2 was outsourced, though (mainly because the Koshiro family was heavily involved).