.stignore synopsis conundrum

If I have .obsidian-mobile on peer 1, and include a pattern of .obsidian-mobile on peer 1, does it not get synced to any other peer, or does it not get synced from any other peer to peer 1?

If the file should not be synchronised from peer 1, should I include the pattern on peer 1, or on all the other peers?

If some files should not be synchronized to (or from) other devices, a file called .stignore can be created containing file patterns to ignore. The .stignore file must be placed in the root of the synced folder (files in other locations are not applied).

So is is to, or from? This is a contradiction in the synopsis. Or, it’s both ways? If that’s the case, how to specify only to or from?

Both directions. If you want the file on device A but not device B, put it on ignore on device B.