Yes. You should be able to use eshop and online play. Even after jailbreaking. But you do have to keep in mind of what you can do, and what you can't do. Jailbreaking is like getting a superpower. There are things you can do that are okay, but some stuff may directly conflict with the online service.
As long as you don't do anything dumb like cheat online or install any .nsp files, you should be in the clear. However, if you want more detail on what to do and not to do, there's a very good "guideline" sheet you can follow.
I should note, if you do plan on modding any game, I would recommend looking into that modding scene. This list is only an "average" look at game modding because each game is kind of their own platform. Some games don't care about mods (like texture mods and such), while games like Splatoon 3 check for any mod you have with some extreme anti-cheat stuff (meaning texture mods are also effected and may cause game-specific-bans.)
Contrary to what people say, I would actually
not use emunand. The reason is due to bans that can be caused from
emunand itself via the mishandling of its setup.
EDIT: Here's a
tutorial you can follow that skips emunand entirely.