Well, first off, the Switch Lite’s screen and the regular Switch’s screen have the same resolution, so the graphics shouldn’t be different.
Onto game play. While LGPE require a regular Switch to do some things (like Pika Papow, Veevee Volley, and multiplayer), I don’t believe that there is any difference between the game play in SWSH when using a Switch Lite rather than a Switch. While looking up the details of SWSH, in case I might have missed something while playing through it myself, I found nothing that hints towards needing to detach Joy Cons or dock the switch to access a feature.
Also, I played Shield on my Switch Lite and it was quite enjoyable, and I didn’t feel that it was missing anything.
Hope this helps! :)