What keyboard are you using? If it's not programmable you're stuck with whatever keys the maker thinks you should have, if it is programmable you just need to change that key position to `~ instead of esc and put esc on a secondary layer.
If it's not programmable you could get software to remap the key, but you'd need to install and configure it on each computer you use and which software would depend on your operating system. Pretty sure this will leave you with no way of pressing esc too...