@Kool ******
the FCD account makes no difference at all to the cost, it just allows you to defer the conversion. Wire transfer to USD FCD or THB account, it will cost exactly the same either way.
In both cases, the real cost is in the exchange rate spread, not the 200-500B. It's not bad with Bangkok Bank and USD, current BBK TT rate is 34.47, midmarket/Wise 34.66. So you pay 0.5% for the conversion with Bangkok Bank. Transferring in 800k this would be a cost of 4,000B (plus the 500B fixed fee). This is ~200B cheaper than doing it through Wise, but ONLY if you get free SWIFT from your US bank.
Smaller amounts are cheaper with Wise as there is a smaller fixed fee component. It's about $20,000 up, SWIFT is cheaper, but only if it's free US-side, and the difference is still pretty tiny.