Removing sims from household

@escapedpolarbear  Teen and young adult/adult clothing isn't exactly the same, so I'm not surprised the game would assign entirely new outfits for the sims once you aged them up.  I think that even when there's a teen and an adult version of the same item, the game rerolls the outfits anyway.

Right now, you have a few options.  If you only want to save the look of the sims, you can bring each one into CAS (enable the testingcheatsenabled true cheat, then shift-click on the sim) and save the sim as a template.  Then you'll be able to add those sims to other households you create.

Another option is to create an adult placeholder sim, have one of your sims make friends and "invite to move in," then instead of moving that sim in, choose the teens from the move screen and assign them to the placeholder sim's household.

Finally, if you want to use a mod, NRaas Mover allows moves that involve teens as heads of household.  So your two teens could move out together without another adult.

@escapedpolarbear  Bring up the cheats console (crtl-shift-C) and enter "testingcheatsenabled true" without quotes.  Then shift-click on a sim and select "Edit in Create a Sim."  Once in CAS, click on the three dots on the portrait of the sim in the user interface, then click the folder icon; this saves the sim as a CAS template.

When you want to see the template, click the six silhouettes in the user interface, which will bring up all the sims saved in CAS, including those saved by the game.  You can filter by age and/or gender, or click the snowflake icon to see only the sims you've created or downloaded.  You can use the template on a new sim you're making in Create a Household, or you can bring an existing sim into CAS the same way as above and then impose the template on that sim, essentially swapping their CAS details for the ones you saved.

Just so you know, the templates don't save a sim's relationships, skills, or anything else about their lives.  This is really just useful for cloning sims: you get a blank slate but with the particular look you want.

@escapedpolarbear  When in CAS, do you see a button with the outline of sim heads above the Undo and Redo buttons?  That's the button I meant.