I can't find the official spectrum rules for Mexico, but from what I can find looking at other products, it appears the upper part of the 5GHz band used by Google/Nest WiFi is not allowed for use in Mexico. That doesn't mean the system won't work, but it does mean any devices that know they are in Mexico or were built and configured for use in Mexico may not see or connect to the system using 5GHz WiFi. They will likely still connect at 2.4GHz, which is significantly lower performance (but longer range). So, just from a "will it work" perspective, I think the answer is "sort of (depending on the client device)".
Beyond that, since these products are not sold by Google for use in Mexico, any issues you run into will not be supported by Google.
So, if it works acceptably for you, and you can live without getting any support from Google, then it may be ok. I think I'd probably pick a product that is sold for use in Mexico myself.