With the biomes being large or biomes being thousands of blocks away, bringing in Mob Traps would be useful. You can click the mob with the item, trapping its size (adult/baby), color (cats different breeds, different colored sheep), and other data with it and then being able to right click where you wanna replace it.
https://peacefulfarms.net/threads/add-a-way-to-put-mobs-in-your-inventory-for-transport.18491/ I feel like it is pretty much the same situation so might not be added.
