I have various households and lots spread across multiple separate saves, which leaves them rather isolated. I would like to be able to port them across the same save so that the household can interact with each other. My intent is to consolidate to a single save.
citymajor as atreya33 says this can be done by saving your latest versions of your households to your library to place in another save. If relationships are lost you can use the cheat cas.fulleditmode to link them again in CAS. (Console players can use this cheat without disabling console achievements because it doesn't require testingcheats to be enabled.) I've done this before with families spread across a few different households and it was just a case of adding them to the original household, linking them again and moving them out again. You may lose career progress though, that's happened to me but there are cheats for that too, to get them back to their place in their career.
You can already do this to some extent. I did this to bring households together in one save for the same reason you mentioned.
You can save a household to your local library. You can upload them to the gallery but your library should be enough if you want them on the same pc. To save households you need to go to the world screen, household manager in the top right corner. Find your household, select edit (pencil icon). This takes you to CAS where you can save them. then place them from your library in another save. You can do the same with lots. Lots can be saved from build mode.
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