so far the only live ones we seen on-screen have been with humans.

Inhumans could be considered hybrids between human and Kree. some episode in Agents of SHIELD season 2 told that the Kree experimented on a number of planets besides Earth. I would guess that the inhabinants of those planets were also sentient beings. same episode told that the experiments on the other planets failed. not sure the fate of those species.

Peter Quill is a hybrid between a celestial (Ego) and a human (Meredith Quill). Ego told that he impregnanted other women and that those children did not have the celestial gene. various pictures seem to indicate that most of the women were humanoid; which might suggest sentient beings. not sure how the other children died; whether Ego killed them or they died through non-killing means.

I would guess that humans have something that other sentient species do not have. but am not sure what that something is.

edit:: found other hybrid groups.

Karolina & Elle Dean; Gibborim (Magistrate) and human (Leslie Dean)

Daimon & Ana Helstrom; Demon (Marduk Helstom) and human (Victoria Helstrom). also Lily; Daimon Helstrom being the biological father.

edit #2:: all the hybrids have powers that non-hybrid humans seem to not have; and sometimes also the the non-human species seem to not have (mainly Inhumans).