I was experiencing a similar issue with and without inactivity and landed here; The vmware-vmx process on mac was just going bonkers 250% CPU. I finally got tired of my MBP sounding like a Vacuum and looked into settings I could change.
I'm assumed it was related to the unnecessary Windows 10 animations/graphics - one of the reasons I wish Microsoft had made the WIndows Classic theme available in WIndows 10.
What seemed to fix the memory hogging issue for me was:
1) Disabling Memory Compression (Using Process Hacker as Admin, I noticed a "Memory Compression" process running on my Windows guest):
PowerShell (as an admin) ---> Disable-MMAgent -mc ---> reboot
2) Disabling the unnecessary graphics
Control Panel ---> Set "View by Category" to "Small Icons"
---> System ---> Advanced System Settings ---> ("Advanced" Tab) ---> "Performance" settings --> ("Visual Effects" tab) --> Set to "Adjust to Best Performance", which should uncheck all the boxes --> Apply --> OK
Now the vmware-vmx process on my mac stays around 50%!
I noticed a slight change in the aesthetics after disabling the visual effects, but I can live with them.