If I search “burst fetters” in Google there are only historical texts in results. So, can I say “Maybe, one bright day humanity will burst fetters of violence and cruelty” if I don’t mean anything related to the slavery but want to say “to get free, to get rid of”?
Grammatically the answer "burst its fetters" or "burst the fetters" is fine, but at least to me, as a metaphor it does not quite flow.
Fetters are bonds or chains, like manacles or a ball and chain, something that prevents free movement. It doesn't quite sound right to say these are made of violence and cruelty. I feel it's slightly more logical to say instead:
break free of their fetters forged from violence and cruelty
However, I'm not sure this is really an English argument, as I think the metaphor would not be quite right in many languages. Systemic violence is used to create bonds, but it is not itself the binding material.