The Chosen Ones

Ferryman has similar themes - a mentor/supervisor from the underworld that's forced regular people to assist them in dealing with the dead - but it's not as goofy, though there's still humor. The Chosen Ones is the opposite side of the coin - a lot of goofy humor, and they're trying to prevent unnecessary deaths.

Both deal with hidden worlds and at least one regular person getting forced to join a team of otherworldly enforcers. Both have heavy comedic elements.