well ive found out that depending on what leagues you use different countries become manageable so the ones that are available are shown
default asutralia provides: Bahrain, Kuwait, Saudi Arabia, Vanuata, Cook islands and samoe
epl unlocks senegal
i think russia unlocks georgia
either france scotland italy spain or germany unlocks martinque
thats all i know so far, so if u chose australia all those 6 teams are vacant
and im assuming using lower leagues opens up more teams...
so i guess u either have to get someone to do this or do it youself to find vacant teams
p.s. all patch 9.3.0 btw