Well, the good news is that there is a workaround that lets you get rid of the charging information on the display: You can simply use Android's screensaver option and make the phone display an all black image when it's being charged. The bad news is that Android's screensaver feature, like Windows screensavers, keeps the display on instead of letting it sleep. The screen will technically remain on all the time that it displays your chosen image. You also have to let the display turn off on its own for the screensaver to show up. However, with no official option to not have the phone tell you how much time is left to a full charge, this is currently the only workaround available.
Here's what you need to do: First, download this completely black wallpaper on your phone. Then, create a folder called Screensaver on your phone's internal storage (you can use the preloaded My Files app for this) and move that black wallpaper image into this folder. Then, open the Settings app on the phone, tap Display, choose the Screensaver option at the bottom, select Photo frame, then hit the gear icon on its right. Here, just tick the Screensaver option in the list and then press the back button to save and enable the screensaver.
Since that Screensaver folder contains only the black wallpaper image you downloaded, your Note 10/Note 10+ will show you that image once you leave the phone display untouched for 30 seconds (or whatever screen timeout setting you have enabled in your display settings) while it is charging. Hopefully Samsung will add an official option to disable the charging message/notification at some point, but right now, this is the only way you can hide that notification if it bothers you to the point of being a nuisance.
