True.
But as KoH realised, an abandoned team with not enough players will (or could) be given players in positions to make a legal formation. So always beware of playing abandoned teams.
nope. not enough player will be punished by 3-0 lost. abandonned team usually has 20% ball possession because they have many player out of his natural position not beacause his formation is illegal.
until he get 11 player to play (14 player inclus injured, cards) player will automatically fill in emty position to complete the last formation used before abandoning