Beyond that, your choice of House will have very little impact on what you can and cannot do in the game. Slytherin players can still be nice, Hufflepuff players can still be jerks, and so on. Your choice of House also doesn’t affect your character’s skills, stats, or prevent you from interacting with major characters.
For what it’s worth, though, your choice of House will play a minor role in your various character interactions. For instance, the game offers a few “companion” NPCs who you’ll interact with throughout the game. If you choose the same House as one of those companion characters, you will be able to interact with them in your shared common room. However, every character will be able to interact with every companion, and there don’t seem to be any notable special interactions that are limited to companions in the same House as you.
That being said, there are some minor NPCs that are only available in your common room. Aside from a couple of unique dialog options, though, those NPCs do not have a significant impact on the game. There are also a few minor dialog differences in certain cutscenes based on your House choice, but most of those differences amount to which House name is said during certain cutscenes. For instance, if you’re in Ravenclaw and talking to a Ravenclaw NPC, they may acknowledge you share a house. If you’re in Gryffindor, that same NPC will likely have much more generic dialog. That kind of thing.
For the most part, though, your choice of House in Hogwarts Legacy won’t significantly alter the fundamental parts of the game beyond which common room you gain access to and the NPCs you encounter in those rooms.
Hogwarts Legacy: Are There Any Quests or Other Pieces of Content That Are Unique to Each House?
While your choice of House will not significantly impact your Hogwarts Legacy adventure, there are a couple of pieces of content that are unique to each House that you should know about.
The first is your starting set of robes and associated cosmetic options (such as an optional broom design available to you later). Basically, there are a few cosmetics in the game that are visually associated with your chosen House. Unless you’re a fan of the primary House colors (Red, Green, Blue, or Yellow), though, then it’s not really that big of a deal.