Filters on backend union remote possible?

V1.55.1
Curious if filters would work using the new connect string syntax with union remotes. From my testing it doesn't, but figured it cant hurt to ask.
Scenario
Remote1:
Remote2:
Both have similar root dir structures but different content. Want to exclude jpgs from remote2. Tried building a union remote with upstream:
Remote1:/:ro Remote2,"exclude=*.jpg":/:ro

But this didn't work. Any way to achieve this vs separate mounts + union on local paths or mergerfs?
Thanks in advance,
Ed

I find it difficult to fully understand your situation, because I miss a lot of information from the parts of the support template that your deleted.

The best help I can offer is therefore a guess that the issue you see is due to this limitation:

Note that the connection string only affects the options of the immediate backend. If for example gdriveCrypt is a crypt based on gdrive, then the following command will not work as intended, because shared_with_me is ignored by the crypt backend:

rclone copy "gdriveCrypt,shared_with_me:shared-file.txt" gdriveCrypt:

Source: https://rclone.org/docs/#connection-strings

I hope this can help you find a solution that works.

I'd probably handle it through mergerfs.

You could use the first mount with the first found policy and the second be the remote.

For moving to second, just use filters on the upload so everything 'stays' on the first mount that you want.

thank you for the replies. The intent was to mount this as a ready only mount, and exclude a file type from the second remote, but I can do two mounts and mergerfs them. Thanks again.