is there any mod/macro that changes the keybind of f3? and if there is, is it allowed?

no and no

@jap_a you can rebind f3 using something like auto hotkey. But you cannot have an f3 shortcut example: f3 b bound to one key. That is illegal. You can’t use a mod to do that.

@aconnx i love the idea of something that doesn't exist being banned

Aconnox is incorrect. You are allowed to rebind F3 with an autohotkey macro or a gaming mouse software. However, there are no allowed mods that do this. First install autohotkey and then create a notepad document with the following:

#IfWinActive, Minecraft
h::F3
F3::

Rename the file with the .ahk file extension (macro.ahk for example) and now when you run it your computer should press F3 when you press H. Replace H with whatever key you want from this list https://www.autohotkey.com/docs/v1/KeyList.htm If you rebind it to a letter make sure it's lowercase, otherwise you'll have to press shift every time.

The rules governing keybinds are that "each game input may have only one key, and each key may cause only one game input" and that "F3 shortcuts (such as F3+C, shift+F3, etc.) can't be bound to a single button." The last line of the above macro rebinds the F3 key to nothing to avoid breaking the "each game input may only have one key" rule, since otherwise you could open the debug menu with both F3 or H.

@Duey did you ask chatgpt to rephrase the javacord command 💀 and why if so, chatgpt forgot to mention ahk needs to be version 1.1 for this script to work

@maskers I wrote it entirely manually, with no AI, and with no knowledge of the Javacord command... I don't know how they ended up so similar.

I have a razer keyboard and use Razer Synapse to rebind it