As I understand it, all transactions are via the US$. So - if your 'home' currency is not the US$ - you still need to be aware (eg using XE.com just for information) of the US$/฿ rates.
My home currency is AUD and when I'm gearing up for a Wise/BKKBk transfer I always check the 3 relevant currencies - US, AUD, ฿. What I often (NOT invariably) notice is that in the morning ICT (when the - I guess - only relevant systems open are Sydney, Singapore & BKK) the AUD/฿ rates tend to be poor. Mid-afternoon ICT when London opens, the AUD tends to rise a bit. And in the evenings ICT when New York opens, the AUD/฿ reaches its peak for the day. (Mostly. There are no guarantees.)
Which - in the broad - means you're mostly going to be best off doing your AUD/฿ transactions sitting at your desk in the evenings.