Can I wire using Wise or use another service, GBP to THB into my wife’s account as a GIFT like I read up to 20 Mil THB per year? Is this actually something that can be done, from what I read it’s there in black and white as a Gift so would like to know if I can actually do this.

Only if it is a gift with no benefit for yourself and you never to benefit from this money. Otherwise it’s a gift with reservation of benefit and its not a gift. I don’t recommend this strategy if you will benefit.

We recommend that you gift the assets overseas and draw up a gift document with a lawyer in the jurisdiction you gift the asset. Then get this notarised, and translated into Thai and kept on file. Also you cannot benefit from the gift at anytime in the future.