>>6274714Bandai used to do that. The 8'' tall ranger figures that saw use from MMPR to around In Space or so was based off a Japanese mold used mostly for reds starting in the 80's. The vehicle rider figures from the 90's where also usually based off Chogokin Sentai figures.
As for why Bandai did original figures, the US marketing really emphasized the civilian identities(especially early on, where you had posters and toys and the like where the Rangers where called by the character's name..I think the first cast shake-up made them a bit more careful with that). So bandai America probably wanted figures that could mesh well with that. Japan even had a few morphing figures later on.
As for the aesthetic differences, i.e. the muscled ranger figures we saw around Turbo and ever since, you can blame that on them trying to imitate domestic superhero lines. And while there are Japanese sentai figures, most of them now are vinyl, which hasn't really done well in the US.