This is more based on vibes and not necessarily as names but:
[name_u]January[/name_u] - Masculine
[name_u]February[/name_u] - Feminine
[name_u]March[/name_u] - Feminine
[name_f]April[/name_f] - Feminine
[name_f]May[/name_f] - Unisex leaning feminine
[name_u]June[/name_u] - Feminine
[name_u]July[/name_u] - Unisex leaning feminine
[name_u]August[/name_u] - Masculine
[name_u]September[/name_u] - Completely unisex
[name_u]October[/name_u] - Masculine
[name_u]November[/name_u] - Masculine
[name_u]December[/name_u] - Masculine
I did not expect there to be such a clear seasonal divide!