Hiii sorry for the late reply, Christmas preparation and festivities have kept me busy!

I think you can totally make the alabaster color work even if there is a "white" mermaid. There are many shades you can use and combos you can go for. For example, I have this white pearl baby and as you can see, she uses white with silver/gray. Meanwhile, this fella over here is still on the "white" part but totally more alabaster. And you can see he works better with warm undertones than the girl which is very cool undertones.