How do I switch the race of NPC's to my own race?

[assassinator88]

I want to change the race of some NPCs in some mods into my own race.

What I've managed to do so far is creating a new race by duplicating an old race with tes construction set and then edit it to whatever I want and then save it as an ESP-plugin.

When I load the ESP-plugin it is possible to use the race I created as a player character, but that is not my goal. What I want to do is changing a NPC to use that race.

I know how to change the race of NPCs and it works fine except when I change them into my own race, because then their bodies will become invisible in the game and the only thing I can see is their clothes.

My guess is that a plugin with a NPC cannot refer to another plugin with the new race and that the new race has to be saved into an esm file instead. But I don't know if that guess is correct and I don't know how to accomplish it.

Any help?