How to modify animals properties in DataPacks ?

Hello i just started a new world and i found a mushroom island with myceluim. I started my base there, brought some villagers, pigs, chickens and so on...
And for sheep, i want to add a simple datapack to allow sheep to also eat mycelium grass to regenerate their wool, how can i do this simple thing ?
i know some basics to like add custom recipes in a datapack but nothing more 👀 
( yeah i know i can use silk touch on some regular grass and bring this grass on my mushroom island, but thats not the plan 😅  )