In English speaking countries, it is legal to give a child any name you wish, as long as it is spelled out in the letters of the
Roman alphabet, so of course
Joey can be a girl's name. I don't know a girl named
Joey personally, but I well remember the actress
Joey Heatherton:
http://us.imdb.com/name/nm0372758/
Jena is a name which has been pronounced either as
Gina or
Jenna depending on how the parents came up with it. The only
Jena I know personally is from Iran originally and pronounces her name as "ZHEN-nah".
Joanie would usually be two syllables as "Joan-ie" in the Anglo community in the USA, but I think some Hispanics do say "Jo-annie".
Joni is usually also "Joan-ie", but there are some women with the name who pronounce it as
Johnny, such as the disabled artist
Joni Eareckson Tada:
http://www.joniandfriends.org/