No Sims showing up

Product: The Sims 4
Platform: Laptop (PC)
Which language are you playing the game in? English
How often does the bug occur? So far, 100%
What expansions, game packs, and stuff packs do you have installed? All
Steps: How can we find the bug ourselves? Have MCCC, increase household limit, turn on testingcheats, import other sims from gallery into random / empty plot, send sim over from target household, shift + click & add to family, repeat from ‘import from gallery’
What happens when the bug occurs? Towns are empty & visiting other households that I placed result in nobody being home. Imported households & all other NPC households have greyed out sims showing that they aren’t home, but say they are home when hovering / clicking their icon.
What do you expect to see? Sims in towns & sims being home when they should be. Basically, other sims other than current active household
Have you installed any customization with the game, e.g. Custom Content or Mods? Yes
Did this issue appear after a specific patch or change you made to your system? Probably
Please describe the patch or change you made. Latest patch, happened after importing third household to same plot, adjusting graphics settings to help reduce lag / strain on system, leaving target household sim on plot & going back out to manage worlds to switch control back to said sim. All mods are updated / say they are compatible w most recent patch