Edited for privacy

Thanks!

Rowan nn [name_u]Rory[/name_u] is fine, especially since they’ll only be cousins. If it really bothers you, you could go with…
[name_u]Tyler[/name_u] nn [name_m]Ty[/name_m]
[name_u]Timothy[/name_u] nn [name_m]Tim[/name_m]
[name_m]Harrison[/name_m] nn [name_u]Harry[/name_u]/Sonny
[name_m]Quinton[/name_m] nn [name_u]Quinn[/name_u] (although a lot of people see [name_u]Quinn[/name_u] as a girls name if that bothers you)
[name_m]Finnegan[/name_m] nn [name_u]Finn[/name_u]
[name_u]Montgomery[/name_u] nn [name_m]Monty[/name_m]
[name_m]Elijah[/name_m] nn [name_u]Eli[/name_u]
[name_m]Lucas[/name_m] nn [name_m]Luke[/name_m]

With [name_m]Leo[/name_m] , [name_m]Jack[/name_m] , [name_f]Bella[/name_f] and [name_f]Evie[/name_f] I would suggest

Maximus - [name_u]Max[/name_u]
[name_m]Charles[/name_m]- [name_m]Chuck[/name_m]
[name_m]Phillip[/name_m] - [name_u]Pip[/name_u]
[name_m]Wilson[/name_m]- [name_m]Will[/name_m]
[name_m]Harris[/name_m]- [name_u]Harry[/name_u]
[name_m]Matteo[/name_m] - [name_m]Matt[/name_m]
[name_m]Christopher[/name_m]- [name_u]Kit[/name_u] / topher
[name_m]Alexander[/name_m]- [name_m]Alec[/name_m]
[name_m]Nathaniel[/name_m]- [name_m]Nate[/name_m]
[name_m]Franklin[/name_m]- [name_u]Fran[/name_u]
[name_m]Andrew[/name_m]- [name_u]Andy[/name_u]/ [name_u]Drew[/name_u]
[name_m]Harvard[/name_m] -[name_m]Harvey[/name_m]
[name_m]Tobias[/name_m] - [name_u]Toby[/name_u]
[name_m]Jedediah[/name_m] - [name_m]Jed[/name_m]

I’ve never heard of someone called [name_u]Rowan[/name_u] having the nickname of [name_u]Rory[/name_u] before? It doesn’t seem like a very natural nickname, why not just call them [name_u]Rory[/name_u] in the first place as it’s an actual name. I prefer [name_u]Rowan[/name_u] for a girl but don’t like inevitable nickname of Row which sounds unfinished. Also the fact [name_u]Rowan[/name_u] has become so trendy and is leaping up the charts at the same time as many other very similar names (like [name_m]Roman[/name_m] with an M) really put me off the name but I did consider it for my daughter until I realised how trendy it is.

I think your cousins have done you a favour here. [name_m]Plenty[/name_m] of less trendy names to choose from.

Here are some name ideas:

Marley
[name_m]Christopher[/name_m] nn [name_u]Kit[/name_u]
[name_m]Wilf[/name_m](red)
[name_m]Barnaby[/name_m] nn [name_m]Barns[/name_m] or [name_m]Barney[/name_m]
[name_m]Peter[/name_m]
[name_m]Nathan[/name_m]/Nathaniel - [name_m]Nate[/name_m]
[name_u]Sidney[/name_u] or just [name_m]Sid[/name_m]
[name_u]Laurence[/name_u] nn [name_u]Laurie[/name_u]
[name_m]Vincent[/name_m] nn [name_u]Vinnie[/name_u]
[name_u]Curtis[/name_u]
[name_u]Eli[/name_u]
[name_u]Ellis[/name_u]
[name_u]Miles[/name_u] / [name_u]Milo[/name_u]
[name_u]Seth[/name_u]
[name_m]Cole[/name_m]
[name_m]Otis[/name_m]
[name_m]Eric[/name_m]
[name_m]Casper[/name_m]
[name_u]Dexter[/name_u]
[name_u]Blake[/name_u]
[name_m]Angus[/name_m]
[name_m]Dominic[/name_m]
[name_u]Idris[/name_u]
[name_m]Chester[/name_m]
[name_m]Caleb[/name_m]
[name_u]Austin[/name_u]
[name_m]Griff[/name_m]
[name_u]Tristan[/name_u]
[name_m]Otto[/name_m]
[name_u]Oakley[/name_u]
[name_u]Cooper[/name_u]

Lennox nn [name_m]Knox[/name_m]
[name_u]Paxton[/name_u] nn [name_u]Pax[/name_u]
[name_m]Boaz[/name_m] nn [name_u]Bo[/name_u]
[name_m]Bowen[/name_m] nn [name_u]Bo[/name_u]/Bowie
[name_u]Asa[/name_u] nn [name_m]Ace[/name_m]
[name_u]August[/name_u] nn [name_u]Gus[/name_u]
[name_m]Shepard[/name_m] nn [name_m]Shep[/name_m]
[name_m]Judah[/name_m] nn [name_u]Jude[/name_u]
[name_m]Hawkins[/name_m] nn [name_m]Hawk[/name_m]
[name_m]Orson[/name_m] nn [name_u]Sonny[/name_u]/Bear
[name_u]Declan[/name_u] nn Dec
[name_u]Beckett[/name_u] nn [name_u]Beck[/name_u]

I think [name_u]Remy[/name_u] and [name_u]Rory[/name_u] would be fine for cousins.

What about …
[name_m]Andrew[/name_m] “[name_u]Andy[/name_u]”
[name_m]Anthony[/name_m] “[name_u]Tony[/name_u]”
[name_m]Dashiell[/name_m] “[name_u]Dash[/name_u]”
[name_m]Elijah[/name_m] “[name_u]Eli[/name_u]”
[name_m]Ezekiel[/name_m] “[name_u]Zeke[/name_u]”
[name_m]Nathaniel[/name_m] “[name_m]Nate[/name_m]”
[name_m]Oliver[/name_m] “[name_u]Ollie[/name_u]”
[name_m]Raymond[/name_m] “[name_u]Ray[/name_u]”
[name_m]Reginald[/name_m] “[name_u]Reggie[/name_u]”
[name_m]Tobias[/name_m] “[name_u]Toby[/name_u]”