Yes we had to get it translated, in the UK there is a Lawyer who does all the necessary actions including the translation and getting it certified by the Thai Embassy in London.
I do swift transfer from my bank in Sterling and get a good rate when it arrives at Bangkok Bank at least as good as wise and get the FTT prefix as was advised to me as necessary.
I wS told different, but anyway I do a Chaps International transfer direct from my bank each month and it costs a standard charge of £20 and for the amount I transfer it is much cheaper than any transfer company, on my bank book I get the correct prefix FTT.