If you have security concerns, then its probably a good idea not even to run the code. But if you really really want to, one could use Virtual Machines with CPU and graphics cards passthrough. In case of Linux, even the Kernel on your machine is reused in the Virtual Machine and the filesystem is nowadays very good optimized too. All of this gives you near native performance. The little bit performance hit I think is acceptable, given that security is high priority here.

I personally wanted to set this up, but honestly I’m too lazy. BTW Flatpak is not a good container, if security is a high priority.