Some black pilots flying with the LoCosts in Singapore, not too sure about SIA but I know they won't hire women in mainline though there are a few in Silk Air.
You may be looked down on for being a foreigner more than for being black. Some of the Asian races think they are well above everyone else on the planet. In Thailand dark skin is a sign of being low class as you are assumed to work outside in the fields or on a construction site doing manual labour instead of in an office.
With more people traveling and incomes rising minds are opening up. When I take a city train in Bangkok I'm rarely the only white person in the carriage.
It's worth trying everywhere, you may be the first.