Likely no to both as Dispel Magic doesn't work like that and even if you cast Detect Magic on her, it's unlikely that you would learn much beyond that she or something she is wearing might be radiating magic. And even if you did sort of suss it out, it's not like Eku is obligated to tell the party anything unless she trusts them.
Eku is a couatl, and the couatl's Change Shape ability indicates that it "magically polymorphs." Per Sage Advice, this means the effect is magical, so detect magic would show an aura around Eku. The rules are a little unclear as to whether this would just be a general aura of magic or a specific aura of transmutation, but personally I'd go with the latter.
However, dispel magic only works on spells, so it would not have any effect.
Noobish DM quesiton:
Sorry if this has been asked before.
Does detect magic work on Eku? and what about dispel magic, will it cause her to revert back to her original form?
Likely no to both as Dispel Magic doesn't work like that and even if you cast Detect Magic on her, it's unlikely that you would learn much beyond that she or something she is wearing might be radiating magic. And even if you did sort of suss it out, it's not like Eku is obligated to tell the party anything unless she trusts them.
Eku is a couatl, and the couatl's Change Shape ability indicates that it "magically polymorphs." Per Sage Advice, this means the effect is magical, so detect magic would show an aura around Eku. The rules are a little unclear as to whether this would just be a general aura of magic or a specific aura of transmutation, but personally I'd go with the latter.
However, dispel magic only works on spells, so it would not have any effect.
Thank you all for your help.