I tried to integrate platformio into KDevelop and I succeeded to integrate it using data from another generated project to QtCreator.
I tried to import it as qmake project but didn’t succeed so I tried as a custom build project and I add the definitions (like AVR_ATmega328P) and the included pathes and it works perfectly.
Please file a feature request here Issues · platformio/platformio-core · GitHub and we will add support for Kdevelop IDE.