Add/Edit Metadata within the Teams File Tab
In the new file experience rolling out, metadata can be surfaced now within the files tab, however, you can't add or edit metadata within the Files Tab itself - you have to do it in SharePoint. You can set default values when uploading files but this is problematic if you have multiple choices (A good example being the column Department where several departments upload files to a single team)
Link to TC thread
Metadata editing is fundamental for our staff. When we train our staff to use the SharePoint platform our biggest emphasis is on utilising metadata and content types, otherwise document libraries end up in a heaped mess. The new file experience is practically useless if the user still has to navigate to SharePoint just to tag a document.
"Oh, you wanna be able to CHANGE metadata in Teams? That's gonna cost ya!"