I'm not sure about AK and PGR, but MHY writers in particular are much more influenced by JP scifi works, since they are all real otakus. The whole company started literally also because of Evangelion and Honkai series had major influences from it. They are TM fans as well as other popular manga/anime series.
Certain writers in their team LOVE philosophy and non-Chinese stuffs. They have references to things like Greek philosophy, the Mahabharata (Bianka Durandal), Shakespeare stuffs, Tagore quotes, Muslim ideology (the main villain plan in HI3rd) and even turned the writer Franz Kafka into a waifu (HSR ver is a bit different from that one tho).
They also are fans of JRPGs and games in general (God of War, The Witcher and BoTW to make Genshin systems for example).
So while I can see Liu Cixin having some influences, I'd say it's barely anything compare to the other things.