When you open a Schwab One international account you don't automatically get the debit card. There is another form to fill out to request one which also gets you checks you can use. I don't use the debit card much to get money from an ATM but if you do there are no fees plus they immediately refund the fee charged by Thai banks. If I remember correctly the daily withdrawal limit is $1,000 but you can only withdraw $500 at a time. If you try and withdraw too much they lock the card and you have to contact them to get it unlocked. I found that out the first time I used it and tried to withdraw the $1,000.
Also when I wire money to my Thai account they show a $15 transaction fee but that is immediately refunded too. So sending money to a Thai bank is free. (Except they don't send in Thai baht so you are subject to the exchange rate the Thai bank gives you.)