JustTooKrul But, if I could run a virtual Android device with GrapheneOS, then that would be ideal since all the privacy issues associated with the emulator and with the OS itself would be moot.
The AOSP build system, and thus the GrapheneOS build system, can build "emulator" targets, but they are most likely not what you are looking for, because they are focused on tasks that developers have, such as debugging applications under construction. The emulator targets don't behave exactly the same way as the Pixel targets (for example, I think the number of secondary profiles is much smaller for the emulator builds). Meanwhile, the emulator doesn't implement the strong security guarantees of the Pixel hardware security processor.
Blastoidea This has been asked before, and as I recall, the answer was “no”.
There is a particular narrow/technical sense in which the answer is "yes", but as far as I know the answer to the original question posed is "effectively no".