Skyler/ar is a made up name from the 80s and has always been ambiguous.
The name has definitely become more ambiguous over time. I was born with this name, and I decided to keep it when I transitioned, as I met many trans women that picked this name for themselves.
I can't imagine this is very common, most transgender people seem to pick a new name.
However, "Skyler" is a 1980s respelling of a much earlier Dutch name that was used nearly exclusively for boys, spelled "Schuyler". Allegedly, it dates back to the 1600s.