Currently, it is possible to crosspost links, but not images. I recently tried to share an image across two communities and had to create two separate posts. It would be a great if image crossposting could be supported in the future.

Just reuse the URL of the first one.

You mean I should fist create an image post. And in the second community I create an Link post using the URL of the image post?
Will the discussions then be displayed in both posts, as with crossposts?

Will Piefed bundle together the comments when done so?

piefed should do that on it's own when crossposting

That would be the best option. Currently there are lot article from microblog that i can't share because there is an image.

I opened an issue about it.

That would be a great idea. :)

Maybe the problem is that picture takes up memor on both server (original server + crossposted one) and the bandwidth to load the picture.

I also would like the ability for discussion posts. Sometimes it is relevant to multiple communities who probably do not have that much user overlap. Going back into my account to find the old post so I can copy/paste the title and content is not that onerous for one post on my computer, but it's more onerous when I use my cellphone to do this. Or if I have a lot of things I'd like to post and am trying to schedule them for the future in one big session now.

Or if I use the link strategy as described in other comments here, simply linking to my first post, would PieFed users in both communities see the comments from the other post?

Thanks for reminding me. I've done it now.

This will be in the next release, v1.8.0

Yes

Great!

Might this be on the horizon too?

Aka. cross-posting text posts:
https://codeberg.org/rimu/pyfedi/issues/996