The transcription of the French podcast about fan-mangas says:
Yes, Salagir is still looking for artists, especially for specials (see further down for which).
He is actually fond of styles different than Toriyama's and will take one if he likes it enough but knows there is a risk of backlash from the readers. So be warned.
About U9 (Humans)
Salagir said that, just like for Piccolo, he was a big fan of Krillin.
Krillin will be in a special someday but there are problems with keeping the artists. There is a big scenario that's very long and some cartoonists have gone MIA after accepting to do parts of it (Salagir said he 'lost' 3 of them already). This universe has an extensive background and maybe everything can't fit in the comic.
About U13 (The Super Saiyans)
Same as for U9, Salagir still needs people to draw U13 specials. The only chapter published was the middle of the story. There is a lot of background about Kakarotto’s story on Earth that has still to be told. He had an artist for the special telling about Kakarotto's take over of Earth but she didn't finish the chapter. He also had a lot of volunteers for the fight Freeza vs Vegeta but not for the rest. He's stuck here because the story is too long and he lacks trusty cartoonists.
About U19 (The Heloïtes)
Soon we shall get more info about this universe. No specials about this universe are drawn or planned ATM (has no artist). For this universe, Salagir would be looking for a cartoonist who is good with : humanoids, special powers, backgrounds (he stressed that one out) and armor.
The Heloites will however be in another special and some fanfics, maybe the Bra/Eleim fight.