Hm... "Dude" is fairly male-coded, so shouldn't really be used in mixed company
"Dudette" is female-coded, so adding that might be a good idea
But that only covers the binary genders, so for non-binary I propose "Duderino"
Putting all that together, the address "Dudes, Dudettes, and Duderinos" (in any order) could be the best way to address a mixed group
@ghost_bird oh yeah, other forms of address are available and work well, but I was just musing on the "dude" schema