Quote PC Games:
"The latest findings show that the console can be charged via this connection, but the previously assumed voltage of 5 volts at 1.5 amperes of current is apparently not sufficient. Battery packs and chargers with these specifications are therefore not suitable for charging the Switch on the move. According to current research, an energy provider that supplies 15 volts at 2.6 amps is required. Such chargers are quite atypical and also difficult to find. However, USB-C power supplies of newer laptops usually fall into the scheme and can be used. With a MacBook or MacBook Pro type C charging cable, the charging process should also be problem-free.

Is it possible to play and charge the Switch at the same time with the power adapter without risk?

We've heard for a long time that the console can react quite sensitively, especially with unofficial (but very innovative) products.

Info that has not yet been published by Nintendo, as far as I know.