I am making a divine rogue subclass inspired by paladin. What I am not able figure out how to do is create a spell casting subclass without cantrips, knows all spells, and prepares spells. No matter what I have a "Prepared Spells" and "Known Spells" on character with this subclass when I click on manage spells. Is it possible to set it to not have cantrips?

I don't think that is possible right now, as the only official 1/3 casters (arcane trickster and eldritch knight) are cantrips + spells known.

Yeah that was my fear. Just wanted to make sure K wasn't missing something obvious

What you can do is, instead of adding a class’ spell list whole, just add all of the 1st-4th level spells you want them to have access to individually under “additional specific spells.” It will still show that they can select cantrips, but there just won’t be any available for them to select.

What's the theme of the subclass? If it fits, only give them options that fit 100% of the theme