PLatformio Arduino board packages

Does PlatformIO use the same board installation packages as Arduino IDE? The reason I ask is because I see only 2 Mega4809 board definitions in the Arduino IDE, but there are 5 in PlatfromIO?

Nano Every and Uno WiFi rev2 both have a reduced pin count. I require a board definition with the full pin compliment. The “Mega4809” option in PlatformIO should be good for Vscode, but I need to work with it in Arduino IDE as well and am wondering whether the library can be copied across or whether I will have to brew my own definition?