As of 8/15/2022 users will be able to merge two 3.2 or 3.4 files together. Please note as of now only data contained in 3.2 or 3.4 files are supported.
*** Documents are not merged right now. Please either download from the original file and upload it to the new file or upload them from your computer's downloads folder.******
See the link about how to download docs in bulk - Downloading Docs