I see multiple options for this, some of which probably are out of scope for this mod and should be separate mods (or already are) ^^
The simplest solution would be to add a setting to just remove the fish from the recipe, although that would mean that Spiderbots are really cheap and, in a quite literal way, a bit soulless. 😅
On Gleba, a good substitute would probably be the pentapod eggs (I mean, they're basically spiders with less legs anyway). For Fulgora and Vulcanus it's a bit more difficult though...
I think the coolest solution would be to basically just add fish to every planet. Fulgora could have some kind of oily fish, Vulcanus could have lava fish, and Gleba... uh... Gleba could have weird fish, probably with 5 legs or something. But I think this would be something for a different mod. 😅
Alternatively, there are mods that add a fish recipe (like this one), but that again introduces the problem of "essentially they are free".
