What does `Ctrl + [` send to the terminal for you if not esc? In my experience these are always the same, so Vim shouldn't be able to tell the difference unless it's a GUI-integrated version like gVim.

Try to run `xxd` and then press Ctrl-V and either Ctrl+[ or Esc, then Enter and Ctrl+D. Typical terminal setups will show the same codes both times (1b0a for esc and \n).

Alt+Space (or Alt+J Alt+K Alt+B to go up, down, left one word from current position after returning to normal mode) is what I often do which should work universally.