Slitherine

In the editor you can check a Customize Force' options which allow players to un-deploy units and purchase/deploy new ones.
How is this supposed to work in-game?

There's no customize force option in the deployment phase.
You can disband units, but this only gets you about 1/3 of the original RPs of the unit.
Disbanding seaborne land units give you back naval command points instead of land command points.
It looks like you can't disband all (land) units, after disbanding a few units the next one is missing the disband button.

Thanks
Erik

WIP maybe for a later update and process, as i also tried it as well

I think it is supposed to work in the current official version.
I asked earlier if this option could be available in campaigns as well, it is designed for single player and MP-scenarios currently.
Then the designer could provide historical OOBs and the player exchange as many of those units as he would like.

for me if it works would make it much more user friendly as i like the option to use what i like and not always what maybe the designer wishes or adds to be used in a given battle, as what if are then possible in some battles, if only they had, had this etc etc