Why would you anyway ? It will just increase the possibilities of corrupting your server... and decrease player experience.
Check this: https://github.com/pmmp/PocketMine-MP/blob/master/src/pocketmine/network/protocol/Info.php /!\ WARNING /!\ Totally not sure if that's it, and as I said before, I advise you to not do it...
no... just not answering, same as I don't answer when someone asks me how to allow all API versions: because it's a dumb idea.