Tip: You can see all games that have demos in the web browser eShop version by filtering. Works with all sales too. : r/NintendoSwitch
Three Nintendo Switch Games Receive Demos On The Japan eShop – NintendoSoup
Free Fire Emblem Warriors: Three Hopes Demo Out Now on Nintendo Switch - CNET
Another Code: Recollection, Nintendo Switch games, Games
Trails Through Daybreak demo is now available on the japanese EShop for the Nintendo Switch. : r/Falcom
A Live A Live demo is now available on the eShop! Demo will allow you to transfer your progress into the full game. : r/nintendo
Japan eShop Round-Up (11/13/2013) - Feature - Nintendo World Report
Rep Kiss Coming December 20, Demo Now Live On JP eShop – NintendoSoup
Nintendo News: A New Demo for Fire Emblem Warriors: Three Hopes Launches on Nintendo Switch Today
Dragon Quest Monsters is on sale on the Japanese Switch eShop. : r/dragonquest