If the etymology is actually gender specific, I don't feel great about it.
If the usage has been heavy enough that people just conventionally assume male, I don't feel great about it.
If the usage (in living memory) has been too light for people (me!?) to have a strong association with gender, I think it's fine. Especially if they "sound like" names that are conventionally feminine. I don't care. I would probably not do it but it doesn't bother me.
Ezra,
Micah,
Asa,
Adriel,
Elisha.
Not
Isaiah,
Joshua,
Elijah.
I don't think of
Dylan,
Zephyr, and
Tristan as mythology names.
Even though technically I guess they kinda are.
- mirfak