UX: compress files and folders and pipe to age under Windows

[graphixillusion]

Hi guys. I'm experimenting some CLI commands to make compression, archiving and encryption on the fly using Windows cmd. I successfully managed to achieve the compression and encryption of one single file using this command:
7z a dummy -tgzip -so filename_to_compress | age -r publickey > encrypted.file
Now i'm trying to achieve the same thing with Folders (with multiple files inside) but i'm not lucky this time. I see that 7z -so switch works just with this formats: xz, gzip, bzip2 and tar which work just with singles files. I'm just wondering what can i use and how to make it works under Windows, using 7z or maybe something else: any idea?
I have another quick question to ask: is it possible to pipe and use age -p switch (with auto generated passphrase?)

Thank you all!

[graphixillusion]

Actually i have found that this command works good:

7z a dummy -ttar -so folder_to_compress | age -r publickey > encrypted.file

What about the -p switch support with this command? Thank you.

[FiloSottile]

Using -p and standard input at the same time on Windows is #196.