is it possible to compute z with rs , priv key and the public key?
Yes.
s=(z+rd)/k
sk=z+rd
sk-rd=z
z=sk-rd
z*G=sR-rQ
If you know private key "d", and signature private key "k", then you can just compute "sk-rd", and it will give you z-value.
I don't know the k , I Know only rs , the private key
(d) of the public key Q , R (rx , ry)
I want to compute the corresponding z of the rs
Is it possible ?