Switch 2 has new magnetic Joy-Con 2 connectors and a separate microSD card reader. Its battery and screen have repair guides, but original Switch parts should not be assumed to fit.
What to check before buying
iFixit score
3/10 · Rubric v2.1. Source: Handheld game console repairability scores (iFixit). How to read the score.
Controls and storage
iFixit has separate guides for the left and right Joy-Con 2 connectors and the microSD card reader. A controller attachment fault and a card-reading fault therefore point to different components. The controllers attach magnetically rather than sliding onto the original Switch rails.
Screen, battery and cooling
The battery, display and fan each have their own guide. The Switch 2 is larger than the original Switch and has two USB-C ports, so listings for first-generation accessories or parts need model-specific checking.