No, there is no problem if a floating voltage exists on VCCE_GXB before it is ramped in Cyclone® V devices. Leakage can occur between VCCE_GXB and VCC/VCCH_GXB which can cause VCCE_GXB to float to approximately 0.3V before the power supply is ramped up.
This is expected behavior and will neither cause any functional failure nor reliability concern to the device.
This can only be observed if VCC/VCCH_GXB is powered up before VCCE_GXB and the regulators were designed to leave the power supplies to float before they ramp up.