Cross platform Maui tooltip works for IOS, Android and WinUI. Please use version 2.1.x for Maui. Version 1.x.x was Xamarin.Forms which should be no longer used.
UWP: implements Windows.UI.Xaml.ToolTip class
Android: implements https://github.com/ViHtarb/tooltip
IOs: implements https://github.com/nmilcoff/EasyTipView
Sample xaml is self explained :) https://github.com/EmilAlipiev/myToolTip/blob/master/myToolTipSample/myToolTipSample/MainPage.xaml