One final reply to myself on this topic..
Thomas Wolff wrote:
What became of the winfsp-fuse project discussed in July 2016?
I'd like to be able to use ftpfs or sshfs in cygwin.
Integration of the project into Cygwin stalled around that time, or was it 2018?
[...]
I've now looked at and installed the most recent WinFSP. The Cygwin glue layer
works as well as it always had. But something is missing: integration with the
usual shell file manipulation commands. For example, one can't 'cd' into the
directory on which a foreign file system has been loaded. That seems like a major
issue unless I'm misunderstanding things.
This turned out to be an issue in Cygwin 3.3.3 but not 3.3.4 or the upcoming
3.4.0. WinFSP is ready to be used from Cygwin.
I plan to rename it FUSE for the upcoming ITP, to avoid
name conflict with libfuse* common on Linux.
Nah, there will be two upcoming ITPs, cygfuse and sshfs. The first will provide
the glue layers (libfuse and libfuse3) that ride on top of WinFSP, and also a
'fusermount' command. The second ITP will be a port of the latest sshfs reference
implementation to Cygwin. sshfs is known to clean-compile against the glue layer
already.
..mark