From my research, USA debit cards with a MasterCard logo on them pay the best exchange rate if you were to withdraw in Mexico. The next card is Discover, then Visa.
But be weary of Bank fees for international transactions. Some charge 1% foreign transaction fees, some charge 3%, and some charge 0%. Preferably get one with 0%.
Aspiration is a newer online bank that charges no fees, and unlimited ATM fee reimbursements. Their foreign exchange rate fee is 0%. It's also a MasterCard. But the bank is newer, and I don't know how long they can sustain this business model, so I wouldn't rely on them 100% till they prove to be able to maintain their no fees business model. Although they are insured by FDIC.
Another bank that I would consider is Discover at their official website. They charge 0 fees. But the ATM will need to accept Discover cards, and I am not sure how abundant they are in Mexico. (if someone can let me know, it would be great). Also the ATM may charge you a fee for using their ATM, and Discover doesn't reimburse you.
Another account is Charles Schwab. They are a Visa, and charge 0 transaction fees, and 0% foreign exchange rate fees. They also have unlimited ATM fee reimbursements. Although they do check your credit.
If all else fails, State Farms Bank charges no fees for their basic checking account. They are a Visa. From what they told me on the phone they charge 0% foreign exchange rate fees, and 0 foreign transaction fees. They also have ATM fee reimbursements up to $10.
Capital One 360 charges no fees, is a MasterCard (I believe) but they don't have ATM fee reimbursements.
I hope this helps.
You can see the foreign exchange rates at the visa and mastercard official website.