@ bgomes: I have a series of landing pages that have already been created and split in different folders (see below). Can I simply add a folder at the top of the hierarchy and move all sub-folders under?
Do you confirm that landing page templates doesn't mean template only but the actual landing pages?
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What about the programs/campaigns? Can we also move them under one workspace?
Or if we only want to do lead partition but keep the viewing/sharing/cloning of all assets, the easiest way to proceed is do as Steven mentioned which is : have a single workspace that all users have access to, implement lead partition to avoid spamming the full DB and give super-rights to global team so they can do WW blasts.