There is a lot of information on one made by a company Albatron circa 2005, but no information on if this product actually came into being. There are some older Asrock motherboards that feature both AGP and PCIe, but past that, nothing that I can find.
The two interfaces were electronically different, so the controller to go between the two would probably add latency, obviously would restrict bandwidth to the significantly lower AGP spec etc etc.