>>10389266>>10389276Ahhh these are adapted from Omoroid, a chibi model kit line from the 80s, with designs by Kunio Okawara (the Gundam designer). Wiki page is only in JP unfortunately.
https://ja.wikipedia.org/wiki/大河原邦男おもしろメカワールド_オモロイドKotobukiya started a spiritual successor to it a few years ago called Evoroid.