Flying in Outer Wilds is like kerbal space program without manouver nodes or orbit prediction. It’s doable if you understand orbital mechanics.
Not really. It’s been a while since I played but IIRC the ship follows straight lines. It doesn’t actually orbit. The planets have predefined orbits but their gravity isn’t fully being modelled on the player’s ship. You don’t need to do Hohman transfers or gravity assists. Flying in OW basically comes down to drawing a bead on a planet and accelerating toward where you expect it will be. That’s what the autopilot does as well. It just accelerates you toward the spot in the target’s orbit that the target will be in roughly when you traverse the distance.