If you’re okay with the ridiculous fees and exchange rates that Western Union charges then go ahead. I didn’t mention a service like Western Union because I didn’t find it wise spending money on double exchange and transfer fees to load a bank account in another continent.
According to NerdWallet, the fee for Western Union “depends on the amount you send and selected country. For transfers up to $1,000, the fee ranges from $0 to $95, while the median exchange rate markup ranges roughly between 0% to 10%”
Most people use a bank like N26, Monzo or Charles Schwab to save money on fees over traditional banks. I don’t see the point in having such an account if it’ll cost you more in fees to fund it than you’ll save in using it. Perhaps you need the account for another reason that I’m not aware of and/or the fees are not important to you.
Based on your situation, it would make more sense to just use cash everywhere or open a local bank account in Mexico. For example, Scotiabank Mexico has no fees when withdrawing on the Global ATM Network.