[2021] Frequent crashes in mid-to-late game: EXCEPTION_ACCESS_VIOLATION

We see two bluescreens in that dxdiag, which are always driver or hardware problems. Were they associated with this game or something else? Next time one happens record the text on the screen please.

Has this always happened ever since you've had this game? Or it was okay up to some point?

The first two lines of that error log point to a problem in user_empire_designs.txt . Are you playing with some customised races, or do you get this issue with the default ones too? You could try moving that file out then starting a new galaxy as any of the default races.  

I'd appreciate it if you could, as a test, thanks!