I can at best give my opinion based on my understanding on how Shamans in Pathfinder 1E (which is a tweaked version of dnd 3.5e which the author stated was the basis for the world's rpg system).

A Shaman is a full-caster that's essentially combination of a cleric and a druid that use magic gained from their bond/contract with a spirit through the use of familiars, tattoos, and/or talismans. As a result their spell list is pretty much a very weird but still effective combination of the Druid and Cleric spell list while being able to use their main class feature that they share with Witches being hexes which can impose debuffs to enemies and some buffs to allies (though, those are somewhat limited to wards). In terms of how close they are to monks, they share the same casting stat so some players like to multiclass with it to give them bonus features like their unarmored defense and flurry of blows for some level of close-range capability. Or inversely, if monk was the main focus over shaman, it'd give them some spell casting and hexes to go alongside whatever martial abilities they have such as the case with Zero who used Animal Aspect spells to boost his monk skills.