One of the things that drove me nuts at university is how much some STEM students mocked a particular set of "...for humanities" math classes without knowing their content. There were some great applications of mathematical thinking that people were shamed about taking.
I'm not who you are asking, but this book https://www.amazon.com/Mathematical-Experience-Phillip-J-Dav... hits some of the philosophy of math. It's been a long time since I've dipped into it, but IIRC, it puts mathematical discoveries and exploration into more of a cultural and philosophical context. I could see this being sampled for a good crossover course that would cover humanities requirements for STEM, and STEM requirements for humanities.
