ouldn’t the difference be explained as staying for a brief period as an individual vs transporting an entire country to a different plane of existence? Also magic in different realms can be entirely different in strength RUMPLE came from mid-evil enchanted forest. The magic there is different from magic in AGRABA, WONDERLAND, Camelot , Middle Kingdom etc wherever magic existed.
Well, for a starters, Agraba is in the Enchanted Forest–that was confirmed by Jane Espenson.
Camelot seems to also be located near the EF because everyone has heard of it and Snow thought she could get Excalibar from the Stone without having to jump realms. The same with Arendelle, it’s located near the EF but doesn’t require a realm jump.
I don’t know what the Middle Kingdom is.
The magic in the places we have been is all the same: you can take hearts in the EF and WL. You can also take hearts in SB. People can POOF into clouds of smoke in any land. There doesn’t seem to be any sort of magical difference anywhere.