1. Don't use shit that monitors in such a way.
2. Where you can't avoid it, do your work in a separate, trusted program and then copy paste it in.
3. Where you can't paste, I'm sure you could whip up an ahk script to 'type' for you from the clipboard.
4. If you're at this step, they've already won.

At this rate, I'm gonna have to go Amish.

There is typing speed 'obfuscators' available, such as kloak, and it's also available in Whonix: https://github.com/Whonix/kloak

It also obfuscates mouse movements (to a degree). But the Whonix docs say it's not as effective as the typing speed obfuscation kloak provides. There's some more context in their docs if you're interested: https://www.whonix.org/wiki/Keystroke_and_Mouse_Deanonymization

As for typing style, I assume you mean stylometry, Whonix also has a page on that here: https://www.whonix.org/wiki/Stylometry

For that, the best known mitigation just seems to be to intentionally change up how you write in certain ways, or to "imitate the style of other known authors" (whatever that means). The docs say that "automated methods like machine translation services" aren't a viable mitigation, but I'm not sure if that includes something like using AI to rewrite your sentences.