As a vimmer, it is very important to have escape key handy.
If you have a HHKB or programmable keyboard (qmk firmware keyboard), then this is no problem
Else, remapping on the OS side is needed.
The following gist is very useful. It covers both Linux and macos.
instead of using .xprofile, use gnome-session-properties for auto apply on startup
I tested it on Ubuntu 20.04 and it is working beautifully.