"Who says that about me?"

Translation: Kdo to o mně říká?

[dsarkarati]

"Kdo to říká o mně?" Is this also acceptable?

[endless_sleeper]

Sounds unnatural.

[tompw89]

Why is that?

[VladaFu]

It is not impossible but would be applicable in very limited situations. You would be asking who is saying that about YOU when several people were saying that about other several people and you would be interesting which particular person was saying that about YOU because other persons were saying that about someone else.

We could accept it as a very marginal solution - and than many people will think it is as fine as the default case which it is not. We may actually do that if we decide it is necessary.