For a hairline crack I sand across it with 220 grit filling the crack with dust. Hit it with thin Ca and then quickly sand some more before the CA glue flashes off. You can’t see it when I’m done- looks like wood grain. I’ve got a cherry bowl I just finished. If I can remember where the crack was I’ll post a picture of it.
If it’s larger I do black CA glue or colored powder, copper dust, something to dress it up and then a pewa if it’s on the outside. Anything over 1/8” gets epoxy and pearlescent dust. My bowls with pewas get way more attention than others. People love that stuff right now. You have to use the right terms: rescued, reclaimed, repurposed, locally sourced, unique, gluten free, free range, humanely raised etc. my epoxy repaired bowls usually sell pretty quickly.