I couldn't an answer to this specific question, but sorry if it's already been asked.

I don't know much about how sims3packs from the store actually work but if I convert them to package files and put them in my game like that, will the game still recognize it as the same stuff in previous saves where I was using store content? Or will it consider the packages and sims3packs to be different items and I will have to replace everything?

Thanks in advance!

It should consider them the same, but you also need to uninstall the sims3packs you were using.

You might want to view this thread on how to do this.
https://modthesims.info/showthread.php?t=665108

As long as the instance ID doesn't change I think you might be ok. It's like cloning an object to make a default replacement in a sense.

I did search that thread, but maybe I missed it because I didn't think it had the answer to my specific question. Thanks for the help!

It kind of does though. As long as the instance ID of the file doesn't change.

I have done the process below to add Store Content to my game - I like to just break it apart so I can make overrides of how things function.

Multiextractor to get from Sims3pack to package

So say you use S30C to break the lock on the sims3pack you should be ok.
The game is looking for that instance ID that is the OBJK number when you open the sims3pack.

So this is why a certain place that has all the store content that you can download explains the process that is not EA...

If you do this and open it in TSRW and rexport it to sims3pack it will act as a standalone object.

The way to test this:
Take your Save and make a copy and rename it (with the store content installed at its current state) - this is your backup as you test this.

Now you should have the Store Content Sims3packs in either your downloads folder or if using CC Magic in one of those folders. I do suggest putting them in a safe folder on your desktop or somewhere in case you need to reinstall for any reason

Uninstall the store content

Create a folder in your mods folder called Store Content

Put your newly created packages in

Clear your caches

Load up your save

Now if things are working fine then you know you did it correctly. Use Save As to create your new save. If things are not working as intended just quit your game.

I do know when I did this I think a couple of objects gave me an issue so I reinstalled them from my store sims3pack.