I am loving [name_u]Joey[/name_u]/[name_f]Joie[/name_f], [name_u]Jo[/name_u]/[name_m]Joe[/name_m], etc as both a boy and girl nickname! I love the idea of [name_m]Jonas[/name_m] as the full name for a boy, and possibly [name_f]Josephine[/name_f] for a girl as I adore [name_u]Josie[/name_u] as well.
Other full names I have in mind are [name_f]Joanna[/name_f] and [name_m]Joseph[/name_m], although I am not quite a big fan of those. What other full names would work well for these types of nicknames?
[name_m]Jonas[/name_m] is cute! Honestly [name_u]Joey[/name_u] for both genders stands well on it’s own to the point it doesn’t need a full name. Go for it!!
I love [name_f]Josephine[/name_f] 
Other [name_u]Jo[/name_u]- names I can think of:
[name_u]Joan[/name_u] (old name, time for a revamp?),
[name_f]Joanne[/name_f]
Jojina (v unusual)
[name_f]Jolene[/name_f]
[name_m]Josiah[/name_m]
[name_m]Joel[/name_m]
Boy names:
[name_m]Jonathan[/name_m]
[name_m]Jonah[/name_m]
[name_m]Joel[/name_m]
[name_m]Jonas[/name_m]
[name_m]Job[/name_m]
[name_m]Johan[/name_m]
[name_m]Joseph[/name_m]
[name_m]John[/name_m]
[name_m]Jones[/name_m]
[name_m]Johnson[/name_m]
[name_m]Joren[/name_m]
[name_u]Jordan[/name_u]
[name_m]Joshua[/name_m]
[name_m]Josiah[/name_m]
[name_m]Jovan[/name_m]
Girl names:
[name_f]Joelle[/name_f]
[name_f]Josephine[/name_f]
[name_f]Joanna[/name_f]
[name_f]Johannah[/name_f]
[name_f]Johnna[/name_f]
[name_f]Jolene[/name_f]
[name_f]Jolie[/name_f]
[name_u]Jordyn[/name_u]
[name_f]Jovanna[/name_f]
[name_f]Joy[/name_f]
I like [name_u]Joey[/name_u] for a girl better that [name_f]Joie[/name_f]. [name_f]Joie[/name_f] would be too complicated.
My favorite [name_u]Joey[/name_u] names are [name_m]Jorah[/name_m] & [name_f]Josefina[/name_f].
[name_f]Joie[/name_f] is the [name_m]French[/name_m] word for “joy”, pronounced kind of like “jwah”, so I’d heavily recommend using the [name_u]Joey[/name_u] spelling.
I love [name_u]Josie[/name_u] as a nickname, so I’d go with that if I had a girl with any name that could even somewhat work with it, such as:
[name_f]Johanna[/name_f]
[name_f]Jocasta[/name_f]
[name_f]Joceline[/name_f] or [name_f]Jocelyn[/name_f]
Or a boy [name_u]Joey[/name_u] could come from (and FWIW I think [name_m]Jonas[/name_m] is already a really good choice):
[name_m]Jonathan[/name_m]
[name_m]Joshua[/name_m]
I’ve tried not to double up…
[name_m]Joab[/name_m]
[name_m]Joffrey[/name_m]
[name_m]Johanan[/name_m]
[name_m]Johann[/name_m]
[name_m]John[/name_m]
[name_m]Johnson[/name_m]
[name_m]Jonah[/name_m]
[name_u]Jordan[/name_u]
[name_m]Joseph[/name_m]
[name_f]Jobeth[/name_f]
[name_u]Jodie[/name_u]
[name_f]Joelene[/name_f]/[name_f]Joeline[/name_f]
[name_f]Joelle[/name_f]
[name_f]Johanna[/name_f]
[name_f]Joia[/name_f]
[name_f]Jolie[/name_f]
[name_u]Jordan[/name_u]/[name_u]Jordyn[/name_u]
[name_f]Jordana[/name_f]
[name_f]Jorja[/name_f]
[name_f]Josanna[/name_f]
[name_f]Josepha[/name_f]
[name_f]Joy[/name_f]
[name_u]Joyce[/name_u]
Girls: [name_f]Jacoba[/name_f], [name_u]Jericho[/name_u], [name_f]Josepha[/name_f], [name_f]Jola[/name_f], [name_f]Joelle[/name_f], [name_f]Jolie[/name_f], [name_f]Jolanta[/name_f], [name_f]Jonquil[/name_f], [name_f]Jora[/name_f], [name_f]Jordana[/name_f].
Boys: [name_u]Jericho[/name_u], [name_m]Jethro[/name_m], [name_m]Jacoby[/name_m], [name_m]Jonah[/name_m], [name_m]Jovan[/name_m], [name_m]Joachim[/name_m], [name_m]Johnson[/name_m], Jacobson, Jonasson, [name_m]Jones[/name_m].