I know you specified an investment trust, but Newton Asian Income Fund is a top choice.
If superior performance could be seen as compensation for low income, Aberdeen Asian Small Companies investment trust is a stand out historical performer (perhaps the emphasis should be on the word 'historical' there).
Nearly 7% of my portfolio is invested in Newton Asian Income, but if starting again today I would possibly choose Aberdeen Asian Small Companies. It currently trades at a premium, but I have seen people say 1) it is worth investing anyway and 2) it is worth waiting as the premium is currently high and should reduce.
Otherwise there are a handful of popular trusts who's names come up frequently on this subject, each of which have their own supporters so ultimately, you have to make your own choice.