unfortunately, that’s not just possible.
the way it currently works,
the core system of enlisted is evolved around squads.
squads are defined entities.
( for example, ger_normandy_flametrooper_2
ger_normandy_flametrooper_1
ger_moscow_flametrooper_2
ger_berlin_flametrooper_1
axis_tunisia_flametrooper_1
axis_stalingrad_flametrooper_1 etc )
meaning, each squad has their own icon, their own settings, their own compositions with few variables for the player to chose.
in which, you cannot just " change it " on the fly.
otherwise you would run into issue such as some modders found ( primarily me ),
where if you reuse the same squads the game will not allow you to spawn with the other.
as the game recognize the same squad already being used.
and potentially soft lock your game.
this also is the other major issue.
squad uniforms are fully embedded within the customization presets of each squad. for example,
ever wondered why some squad have gray pants in the german army, but older ones do not?
that’s precisely because the customization is not actually " campaign based " as the game seems to imply.
instead, all squads have 4 different ( or more / less ) presets, in whom each are different from other squads. hence, if you were to add a helmet, you would have to add this helmet over 40+ squads across 120+ presets individually.
which it’s why we don’t get new cosmetics in the customization pool very often.
as the Ex community manager stated, there is not enough time, or money to fix the core system of this game.
so they instead opt to add more squads instead, and probably never bother with cosmetics at this moment in time unless it will get out of hand, or will change this system in the future.
beside, the cosmetic person working with presets uniforms appears to be only one.
all to say, it would be much better and easier to introduce legacy squads back.
but they probably don’t want to, as working with fewer squads would be more manageable.