This is a difference that is used in Belgium, which you could see in overpass.
Where the law indicates the difference by means of a letter A and B and P.
This should be translated into world OSM access tags.
In the Netherlands we use mofa (snorfiets) and moped (bromfiets), the law makes the difference between those two groups.
Rules in the law also stipulate that a snorfiets (mofa) must follow the rules of the bicycle, unless otherwise specified, so a bicycle icon also applies to a mofa (snorfiets) moped. https://forum.openstreetmap.org/viewtopic.php?id=66453