Your taste may vary on if these ships are good or not.
Dr. Kamikazi X Constantine (That shirt Constantine made Kamikazi in Traffic Slam and his seemingly jealousy in The Babysitter support this, I forgot or don’t know if there are other moments that support this).
Bjorn Bjornson X Princess Justine (They are both antagonistic children who are unusually advanced for their age).
Bjornbot/Brother Bjorn X Mona Lethal (Both evil robots, and Robotboy had a crush on Mona, and Bjornbot's rival is Robotboy. And anyway, Robotboy doesn’t like Mona now due to her attempted murder of Tommy and Gus).
Von Der Schnitzel X Principal Culpepper (Both are evil and similar shaped).