Any way to merge one catalog to another, or the changes if the raws exist in both places?

Hi all, I run Classic on both my laptop and desktop.  Both are Mac, same OS, same LR Classic versions.  I don't use online or creative cloud storage for several reasons, but the largest being that most of my photos are taken on destination trips, and then I do quite a bit of editing in Classic+Photoshop on plane flights, which seem to be the only time I can disconnect and enjoy editing photos.  However, if I don't have that time, the rest end up on desktop for me to edit there.

I export my keepers easily enough from the laptop, and sync its entire Lightroom directory structure to NAS when back at home so everything is backed up, but I'd really love to merge those missing dates into the desktop copy.

Is there any way to accomplish this, whether via export/import, manual work, etc?  I have all the raws, they're foldered by date so I can also easily sync the directories in, but that of course does not bring the changes in that only Lightroom knows about so I end up with a bunch of unedited photos.

Thanks!