I saw you had posted in the Arclight thread, you can also have a look in this thread Gnomish Gnoleplay where some other guild is mentioned. There’s also a Gnome community https://worldofwarcraft.com/en-us/invite/0BkZGpSYpK?region=EU&faction=Alliance I just joined it myself and it doesn’t seem overly active but can’t really say since I as I said, just recently joined it 
there’s also [A-RP] 🛠 The Gnomish Air Corps - Gnomish Fun! if you’re into flying machines 
I’d also like to know if the Arclight guild is still active, I think it’s kind of is