Remove 'CMD+i' shortcut from Terminal
[I just realised, this won't work for Esc, as it's not considered a valid modifier, but I'm posting it just in case it may help someone, somewhere...
Best guess is something like BetterTouchTool might be able to do it]]

You can do it in System Prefs > Keyboard > Shortcuts > App Shortcuts...

The trick is to first replace the command you don't want with junk, then add the one you do want..
...however, this method will only work if the function you require also has a menu entry.

example, using Terminal as I don't have vim...

first, replace your 'bad' command with junk





Then you're free to add your new command - if it exists as a menu item.