I know a Grace, a Hope and a Faith, all boys. To me they seem to work okay.
Are they of African heritage? That wouldn't sound out of place to me, but it would seem very strange for a European male.
Also boys called Jesse, Valentina, Bela and Sou. However these are boys' names that sound like girls' names not girls' names crossing over.
Jesse is a boy's name - there was a male Jesse in the Bible. There was also a (male) Elishah, but very close variants of that (in spelling and pronunciation) are now considered 100% female names - to the extent that any boy given the name would probably be teased for having a 'girl's' name.
Are Valentina and Bela from central/eastern Europe? There are a number of continental male names ending in 'a' - Andrea, Nicola, Sacha etc. - that are perfectly fine for people from there but would sound weird for a British person. Also, I'm guessing that 'Sou' isn't really related to 'Sue' (as a diminutive of Susan or Suzanne), other than happening to share the same common single-syllable sound?
The old crooner Val Doonican (younger MNers: ask your GPs!) was actually called Valentine (not Valentina, though), and he stated once that people thought his full name sounded like a woman's name. Unlike Pat or Chris, though, I can't actually think of a male name for which Val would be a short form. Valbert (husband of Ictoria)?!?!?!