what you mean? you can maybe use $player->sendTip("hello"); and then set the \n at the string text to be on the right place, like pc.
Rather than asking, why not just experiment yourself by sending new packets to players? I've seen recent commits of dktapps where he found out the new scoreboard related packet's needs/values and completed the packets. So it's basically implemented but not documented (some of them are documented). Wait for documentation/guide to come out or someone to do the thing as an example in GitHub/poggit. Check pocketmine/network/mcpe/protocol for the new packets, open the files, read it. Learn from api, use forums when you're completely stuck at something, if you don't try yourself first, forums can't help either because you're not trying!
UPDATE: I've experimented with SetDisplayObjectivePacket and SetScorePacket. First packet seemed to crash the client when sent and 2nd packet didn't do anything. Yes I've put all values right (criteria to dummy, slot to sidebar and so on..) So maybe it's for 1.5.x beta or I'm doing something wrong :thinking:
I'm assuming that a packet is still missing, after seeing bukkit api, there's actually 3 packets for score boards (not including remove objective packet)
There are many packets in BE that largely differ from the Java edition. They don't just copy-paste the Java code , for example the InventoryTransactionPacket.