org-xournalpp VS embrace.el

Many packages like org-krita/org-yt/org-excalidraw/org-xournalpp allow custom files to be displayed inline by means of a custom link type. However, they don't work when the file is linked as an attachment, which makes me think that there may be a better way to achieve this.

By Xournalpp-mode do you mean org-xournalpp? I was not able to find a package named Xournalpp-mode.

When writing in org-mode (most of my research writing) I use org-xournalpp to add rough sketches and figures.

I haven't had a chance to try it out but you might be interested in https://github.com/lepisma/org-krita and https://gitlab.com/vherrmann/org-xournalpp

https://github.com/paldepind/composable.el https://github.com/cute-jumper/embrace.el

For changing, deleting or adding Latex environments or other delimiters around text I use embrace instead of something like your change-env. With some customization to better support Latex it works pretty much like change-env, only it can't handle labels, and it's also useful generally for any kind of delimiter (punctuation, html tags etc) across Emacs.

- Embrace (the ``xah-insert`` family of commands are not powerful enough for parentheses editing imho, and most of them are extremely useless). I've managed to configure Embrace to behave almost exactly like XFK, just with a wider range of features.

You can try these packages. A bit outdated, but I hope it works: https://github.com/cute-jumper/embrace.el

https://github.com/cute-jumper/embrace.el This may be what you want. I like it a lot. It's very configurable, comes with a Hydra-like interface but you can also just use the commands in your own keymap, and has a lot of capabilities.