Using the LEASH ALL MOBS mod, you can do a lot of things in MCBE. In total, the mod allows you to put on a leash on more than forty creatures in MCPE! There is absolutely everything on this list – from cats to an under-dragon.
The modification works in Minecraft on Android on version 1.16. It does not replace any textures or resources in Minecraft PE. And LEASH ALL MOBS should not be taken seriously – the addon was created in Minecraft Bedrock Edition solely for fun. Have a good mobs hunt!