Hi,
in italy for sport climbing we use the only French grading system.
The grade:uiaa is used only in the mountain route without fixed anchors.
Anyway both scales are present in wikiosm and "Map the usual one(s) for the climbing spot, i.e. commonly used ones"

osm.wiki/Climbing

Grazie Ivanbranco. non ero a conoscenza dell'utilità.