Do you want a cute companion for your adventure? With this add-on, you can do what you want.
This add-on allows you to add original MOB that can be tamed.

This add-on has been upgraded to Ver.3.

Bugs have been fixed in response to Minecraft updates.
After taming "usagi," it is now possible to make him "sit."
"usagi" will no longer attack piglin hunter or zombie piglin unless the player is attacked first.
"yukidama" now drops when "usagi" dies. "Yukidama" can be thrown.
The attack power of "yukidama" against some monsters has been increased.
For example, ghast, blaze, wither, magma cube, etc.

Usagi Addon Trailer(YouTube Video)
https://www.youtube.com/watch?v=W3dNQ2hAv_g

Usagi adddon

Original MOB:Usagi
This original MOB occasionally spawns in plains, deserts and flower forests. This MOB can be tamed with emerald carrots. When you tame, the MOB will follow you in a "MEIDO" costume. It will fly when you tame it.
If a monster is nearby, it will attack automatically. Attacks the MOB that the player attacked and the MOB that attacked the player.

Usagi's health is 50. When tamed, the Usagi's health will be 20000. Tamed Usagi can be recovered with carrots and Emerald carrots. The amount of recovery of Usagi's health is 100 for carrots and 5000 for emerald carrots.

This original MOB cannot be bred.
And you can also name it using a name tag.

Usagi

New item
Emerald carrot: Emerald carrots can be crafted from one emerald and one carrot.

craft

Usagi Ｏriginal MOB