You can turn off the sync feature till an extent on your device i.e. either confine it to be synced when connected to wifi else on Mobile Data.
Under the Settings option, select the preferences and under that you can find the option to turn off sync feature for your account.
Additionally, the syncing only happens for the files to get saved onto the CC libraries which are connected to your Adobe ID and therefore whenever you sign into any application using that Adobe ID the files would appear under the CC libraries but won't get imported to the app unless you do so.
Let me know if that helps.
To turn off syncing globally, go to the CC Desktop app, click the three dots and choose preferences. From there, go to the Creative Cloud tab, then choose the Files tab from the next level; uncheck Creative Cloud Sync and all syncing will stop. No files are deleted from your machine or device, but you won't have them sync.
Be aware that includes all of your library assets (colours, PS layer styles, patterns, graphic assets), fonts and other CC files, too—you'll be losing a lot of the advantages you have with your membership.
Hope that helps.