All known companions you can befriend in Hogwarts Legacy

gamepur.com:

While you will be the main character of Hogwarts Legacy, that does not mean you are the only person patrolling the halls of the school of witchcraft and wizardry. You will encounter plenty of other students in your adventure, with some of them becoming your friends and joining you on your mission. Here are all of the companions we know about in Hogwarts Legacy.

As of this writing, we have only been introduced to a few companions in Hogwarts Legacy and do not know much about them. We do know that these characters will be able to teach you new abilities as you get to know them and likely will have their own companion missions focusing on them. We will update this post when we know more.

Natsai Onai is a Gryffindor student who loves adventure. She wants to be a hero and show that she is looking out for the good of all.

Poppy Sweeting is a Hufflepuff student who loves magical beasts to the point that she connects with them easier than she does with other humans.

Sebastian Sallow is a Slytherin that likes to fool around and does not mind getting in trouble. He doesn’t appear to be made out as a bad guy like usual Slytherins are, but he apparently has a dark family past.