I don't see any reason why this shouldn't be implemented.

could make a separate gui for books possibly, but this would not really be useful for dupe hunting

There have been dupes involving book GUI, e.g., the recent Hypixel's Pit duplication glitch (https://youtu.be/k4h42PG-Cfw). Manipulating the /report GUI may uncover new dupes in both Hypixel's Pit and Hypixel's Skyblock.

Ill look into it in a bit then

You might want to look into cmd utils (https://github.com/Coderx-Gamer/cmd-utils), it will probably work better for stuff like this, if it doesn't work well then I might add some features to either mod.

Use CMD utils for this