Technically 4 telepaths with Xavier. It would have been easier to just retcon her as the real Betsy way back then when the Asian Psylocke was barely a few years old. Certainly a better choice in the early 90s to do this retcon than Claremont retconning Bloody Bess as Betsy in the late 2010s. My guess is that because Asian Psylocke sold well as eye candy, they decided to keep her and it was easier to justify keeping her if she was the original character with an established history and background. I don't think British Betsy was very popular that way so this is why they kept her around in the background before finally confirming she was really Kwannon and killing her off since they didn't need a copy. I
t's all really badly done and they should have just established Asian Psylocke as a Hand sleeper agent in the team. Claremont kept giving hints about that and Psylocke's true loyalties before he left the book since he wanted to set up The Dark Wolverine Saga where both Logan and Jean would get corrupted by the Hand. I'm sure Betsy would have been a big part of that storyline having been through the process before and she may have been instrumental in saving them as she was in X-Men Forever Annual #1 where she, Kurt, Kitty, and Jubilee save them from the Hand.