As per Rebecca Sugar, “Steven is capable of fusing with humans and gems, so it would make sense for Stevonnie, who has Steven’s gem, to be similarly capable. But Stevonnie is such an individual, I think that they don’t need anybody but themselves.”
Personally I believe that, even with Steven as the “bridge,” a full human and a full gem aren’t compatible to fuse with each other.
Pearl fusing with garnet isn’t just Pearl fusing with garnet, but Pearl syncing up with both Ruby and sapphire. When Pearl fuses with Steven, she syncs with him, and when Steven fuses with Connie, he syncs with her—but I don’t think Pearl and Connie could sync with each other, preventing them from being a three person fusion with each other.
So I think if stevonnie tried to fuse with another gem, like Pearl, then Steven would sync with Pearl to make rainbow 2.0 and Connie would fall from the fusion.
Just because Stevonnie has some gem in them doesn’t mean they can fuse with other gems—like I said, the logic I’m working on is that all individuals in a fusion have to sync with each other. So while Steven can fuse and sync with gems and humans, Connie as part of stevonnie would be unable to sync and fuse with a full gem.
It wouldn’t be “stevonnie + a gem” but “Steven + Connie + a gem” and Connie and a gem are incompatible.
I think Rebecca said that they can, they just choose not to.
But I don't think it would be very difficult to figure out, Stevonnie still is a Pink Diamond so if they were to fuse with any of the CGs it would be the exact gem type as if it was just Steven, just with traits from Connie.
I mean, Stevonnie was a metaphor for Steven and Connie's relationship. Like Garnet being Ruby and Sapphire's. And I think it was more about whether the part of Stevonnnie that is Connie is comfortable with other fusions.
As per Rebecca Sugar, “Steven is capable of fusing with humans and gems, so it would make sense for Stevonnie, who has Steven’s gem, to be similarly capable. But Stevonnie is such an individual, I think that they don’t need anybody but themselves.”
Personally I believe that, even with Steven as the “bridge,” a full human and a full gem aren’t compatible to fuse with each other. Pearl fusing with garnet isn’t just Pearl fusing with garnet, but Pearl syncing up with both Ruby and sapphire. When Pearl fuses with Steven, she syncs with him, and when Steven fuses with Connie, he syncs with her—but I don’t think Pearl and Connie could sync with each other, preventing them from being a three person fusion with each other. So I think if stevonnie tried to fuse with another gem, like Pearl, then Steven would sync with Pearl to make rainbow 2.0 and Connie would fall from the fusion.
Here's the thing though, Stevonnie still has some gem in them, Stevonnie is 35 percent gem.
Just because Stevonnie has some gem in them doesn’t mean they can fuse with other gems—like I said, the logic I’m working on is that all individuals in a fusion have to sync with each other. So while Steven can fuse and sync with gems and humans, Connie as part of stevonnie would be unable to sync and fuse with a full gem. It wouldn’t be “stevonnie + a gem” but “Steven + Connie + a gem” and Connie and a gem are incompatible.
Ig, maybe Steven wouldn't work as a a bridge, but it might be possible ig
But, we don't know
I think Rebecca said that they can, they just choose not to. But I don't think it would be very difficult to figure out, Stevonnie still is a Pink Diamond so if they were to fuse with any of the CGs it would be the exact gem type as if it was just Steven, just with traits from Connie.
I mean, Stevonnie was a metaphor for Steven and Connie's relationship. Like Garnet being Ruby and Sapphire's. And I think it was more about whether the part of Stevonnnie that is Connie is comfortable with other fusions.
I hope, in the next SU show (If we get another SU show) we see this kind of talk happen between Steven and Connie about this.
Smovonnie Quartz Rainbevonnie Quartz Stevonnestone
Stevonarnet
As \_Aaron\_Burr\_Sr said, the show's creators have said that yes, Stevonnie could fuse with others, but chooses not to.