.....how would you organise them militarily ? I can picture while they may be placed into the air forces of a country, I think it may be an incentive to merge the air forces back into the army due to the versatility of the variable fighter allowing for easily accessable organic air cover.
Alternatively, I think that it might cause issues relating to interservice rivalry within the air force and the army as variable fighters can serve as mobile ground assault units in addition to the role of aerospace combat