my cats are lonely

well, ignore the title, they aren't 100% lonely.

duckpuddle of riverclan is a serene, sociable, kind cat who can have a sarcastic tongue around those who she doesn't like. While she does value peace, she's willing to fight (physically or verbally) for what she believes in. She doesn't announce her beliefs, though. She discreetly keeps them to herself. She has anxiety, and she's rather self-conscious about that, but she does a good job at hiding it.
She's willing to befriend cats from other Clans, but she may be a bit wary around ThunderClanners and WindClanners.

wisteriapool of thunderclan is a timid yet passionate and idealistic cat who loves her family more than anything. She has social anxiety, so that plus her shyness makes it extremely difficult for her to start and carry on conversations and/or interactions with cats who she doesn't know. She doesn't like cats who have an outwardly rude or threatening demeanor, and she's more willing to approach a cat who looks like they'd be kind and accepting.
She's willing to befriend cats from any Clan, even if she is a bit afraid of RiverClan.

poplartooth of skyclan is a judgemental, stubborn cat who's honesty can, more often than not, come off as harsh and offensive. He doesn't like apprentices and kits (except for Drizzlepaw) and he thinks that they're annoying and nosy. It took him a while to come around to Mumblefoot, so don't expect him to immediately like you. It'll take a bit of time. He believes strongly that the first impressions of other cats are extremely essential. This means that he'll always see you as the cat that he first met you as.
He is not willing to befriend cats from any other Clans.

dovestream of windclan is a sociable, bold, tomboy-ish cat who isn't afraid to speak her mind or get a little sassy with those she doesn't like. She's defiant, stubborn, and enjoys arguing. Her spontaneity makes it difficult to know what she'll do next. It's quite easy to become her enemy, and it's easy for other cats to see her as annoying. She enjoys being with toms more than she-cats, not because she wants a mate, but because she feels like she fits in with them, more.
She's more open to befriending windclanners, but she's not totally opposed to befriending other Clan cats.

i didn't include newtface because he's dying soon and he's too emotionally dead to even consider approaching anyone.

Featherheart will judge you. Only the best friends for his little sister. <3

I can see Nutfur and Duckpuddle getting along nicely.

Swoopnose could be Wisteria's friend. His usual attitude is laid back and friendly. Would she be willing to shun him if she found out he was sharing ThunderClan secrets with an enemy clan and training in secret with his SkyClan father?

nutfur and duckpuddle would be excellent friends, you're right.

wisteriapool, if she found out about what swoopnose was doing, would probably keep it a secret from leopardclaw and blizzardstar if swoopnose asked her not to tell.

however, she probably would tell one of her siblings.