I think the tutorial is pretty straight forward and fairly easy if you read yourself through part 1-4.
Peer determines the overall Player object and counts for both, Host and Peer players.
There's a great example included in both Construct 2 and 3 which comes with all the multiplayer basics and fits the tutorial given.
The game loads specific Host Group events in case you're the first person to enter an empty room.
All players following later up will load the Peer Group events.
This is required for the Host to handle the Data being sent from the Peers to the Host since this is an authoritative Host scenario.
So that's the only major difference between Host and Peer when it comes to the events.
Your suggestion of using 2 sprites seperately (host and peer) isn't efficient and would require you to sync double the amount of data between players. In short: No that's a really bad idea.
So the tutorial shows you sort of a best practice way which i can only recommend to follow.
Checkout the example. Read all the tutorials again. Understand how data is being synced between Host and Peers. Then go on from there.