I just want to share my recent usage of Mp3tag Tools together with some of my favorite Matroska tools, especially since Mp3tag can tag MKV and MKA.
Also thank you, kind author. I haven't declared here before, but I think Mp3tag is the very first tagger I use which supports emojis and the like, thus I am able to preserve such unique metadata with it. Lately or not so long ago with the help of the kind author of chapterEditor, the author of MKVToolNix updated his program to support it as well. Thus all three can handle emojis now.
So I might as well inform here to you fellow Users that you can preserve emojis too, for example tagging with Mp3tag. No more fear of losing such metadata when for example the MKV or MKA is remuxed many times over by MKVToolNix or if edited by chapterEditor. Of course the display could still be empty square boxes, but they should be correct. Simply verify by using MediaInfo's HTML View.
I use Mp3tag to batch tag MKV's often. I often download videos from YouTube then remux them with FFMpeg first then finally MKVToolNix into the MKV container. And perhaps just this two or three years ago when emojis and the like appeared in YouTube as titles and the video's author's comments for example.
MKVToolNix GUI by Moritz Bunkus
MKVToolNix GUI's Header editor tab
MKVToolNix GUI's Chapter editor tab
MKVToolNix GUI's Multiplexer tab
chapterEditor by HubbleC4
chapterEditor's Matroska Tools tab
-l ceMTTags "%_path%"
chapterEditor's Chapter editors tab
-l ceMatroska "%_path%"
Other programs I use simply work with