I like all three names to a certain degree. For one I prefer
Allison spelled
Alison. All three names can have the nn
Allie, though I feel
Allison would also be the mostly like to be shortened to
Allie. With
Alexis the nn-s
Lexi and
Alex could also be derived.
Alyssa could also be nn
Lyssa. All Allisons I have known have always seemed to just have the nn
Allie /
Ally.
I like
Alexis Maeve the most. Theoretically any names go with siblings names. to me
Alyssa,
Allison and
Alexis all go well with
Claire as a sibling. Maybe with the mn
Mae instead of
Maeve, just because it seems more in the realms of a "normal" name rather than the less popular and known
Maeve. In that case
Alexis Mae is also very nice and maybe "
go" with
Claire Nicole more.

My 45 PPs - names in profile