Does switching the keyboard language (literally) works? I’ve used US format keyboard along all my life, a couple days ago I bought a Macbook Pro 13’ mid 2012 in in Mexico it was way more cheaper and with no issues at all with the computer, but I’m not used to that keyboard keys, I wanted to know if it’s possible to swap the keyboard language not just on software but in hardware as well.
If you want to replace your existing hardware keyboard, you need to contact an Apple store or other service operation directly yourself and ask whether that is possible and what the cost would be.  Whether the right parts are available somewhere for a 7-year old machine is hard to know.

An easier solution would be to try using a "skin" over the existing keys or otherwise mark them to meet your needs.