Any way to trigger home button with L Joy-Con only?

Solution 1:

I'm pretty sure the only way to reach the Home Menu is by using a Home Button, on a controller which has it.

Same goes for the Share Button when wanting a screen capture.

Solution 2:

With the new button mapping system, you can assign the home button function to one of the buttons you normally can't use when your joy-con is in horizontal mode. I personally use the ZL button on the left joy-con because the L button is much easier to accidentally press when playing a game, and is more sensitive to pressing it down generally. This way, I still have all of the normal functions of the left controller, but I also have the ability to go home

Solution 3:

You can get to the HOME Menu without the right joy con. (or pro controller.) Put the console into Sleep Mode then wake it up. Press Featured News. Press Back.