These are some selfcest ships that there should be more of (or any at all) and a couple of name possibilities for these ships I just randomly thought of or found.

1p Japan x 2p Japan
Ship names: Sushi Roll

1p Prussia x 2p Prussia
Ship names: Awesomecest
( I personally like this ship best when 2p Prussia is Seme lol )

1p Belarus x Nyo Belarus
Ship names: (none)

1p China x 2p China
Ship names: High Panda

1p Austria x 2p Austria
Ship names: Pianocest, Demon Duet
( Currently one of my favorites at the moment )