RAM and processor requirements for resource hungry Windows apps

I use Parallels on my MacBook Air to run a Windows 10 VM. I'm looking to upgrade soon to a MacBook Pro, and transfer my VM across. As the latest MacBook Pros don't allow for adding more RAM at a later date I'm keen to ensure that I have enough RAM from the start. The standard setup comes with 16GB, or I can pay extra for 32GB.

16GB seems like it should be enough for most things, but I'll be using assistive software like ZoomText Fusion (https://www.zoomtext.com/products/zoomtext-fusion/) which can be pretty resource hungry. The official system requirements (https://www.zoomtext.com/zoomtext-and-fusion-system-requirements/) say that 8GB is recommended. Would 16GB of RAM overall be enough for me to run my Windows VM and also to comfortable use macOS apps at the same time, or should I go for 32GB?

Similarly, would it be worth going for an 8-core i9 processor over the standard 6-core i7? In my experience Macs can be pretty overspecced for a lot of day to day stuff, but in this instance I'm thinking the extra processing power might be useful.