Your solution would work in a round-about way, but I would still like my suggestion to be implemented as it has some advantages:
1) It’s a 1 step operation (ie. open find/replace, with Incremental Search and Use Output Bar enabled, and start typing your find/replace expression). Yes, automating with a macro would help with this issue, and I like the way that EmEditor can be scripted, but it doesn’t feel as intuitive for what I’m trying to do.
2) Most importantly – You get immediate, real-time/incremental feedback on the results via the Output Bar. This is a killer feature.
Plus, as I’ve mentioned before, EmEditor already has most of the required functionality built-in, so I can’t believe it would be that difficult to add this feature. Essentially, it needs one main thing – a “Use Output Bar” option for the Find/Replace dialogs which, when enabled, will output all Find matches (if on the Find dialog), or all the Replacement matches (if on the Replace dialog).
If “Incremental Search” is enabled the Output bar is updated in real-time with the results, and if “Incremental Search” is disabled the results will only appear in the Output Bar if Find All button is pressed (NOTE: you can add a Find All button to the Replace dialog which causes all Replacement matches to appear in the Output Bar).
The one other thing you caould add to both dialogs would be an “Extract All” button which would create a new document containing all find results, one per line.
You could take this feature quite a bit further than this, but I would be happy with the above features for starters.