Lightroom CC and Classic double local originals

Hi, I've been stuck for some time, and it's time to seek for a help 🙂

I wanted to move to the CC, being able to edit my images on my iPad and having all my files instantly synced accross all my devices. However, as a long time Lightroom Classic user, I miss many features, so I though, it would be great if I can use the same library stored in the cloud to edit photos in Classic when I'm on my computer. Hovewer, I faced some storage issues, having both my catalogues storing originals and doubling the required space. Ideally, I'd like to keep originals in the cloud and in one of the catalogs, while another keeps only the smart previews.

This is what I did:

1. I have migrated my entire library to the Lightroom CC.
2. I deleted my Classic Catalogue and raw files from HDD (I have backup on the external drive, just in case).
3. I created new Classic Catalogue and turned on sync.
4. Both CC Library and Classic Catelog store originals on my HDD, even though I checked the option in CC to store the copy of all smart previews locally.
5. I tried checking and unchecking smart preview option, restarting Lightroom CC, but it didn't change. The CC Library size remains the same no matter what.

Thank you for your help.