It's too early to talk about this. Currently, not all characters' outfits have even been implemented yet (it seems the plan is for full implementation in the Early Access version at the end of this month)...so even less can be said about collecting them. Furthermore, the developers themselves seem to have an intention to remove this feature. Additionally, in the case of Honey Village, due to the multiple race settings, each outfit is restricted to a specific race. If you try to apply the ID directly to another race, the character will just become completely nude... (The same applies to hair, which is also race-specific; using the wrong ID results in the character becoming bald.) Therefore, a system for collecting outfits to dress up captured NPCs makes even less sense.
PS: Outfits can be displayed normally on SD characters even if the races are different, but they immediately turn into nudity once they enter an H-Scene.