The Cuban vlogger TecnoLike Plus has already purported to have reviewed the Google Pixel 4a's cameras well ahead of its launch. Now, the same source has leaked this phone's relevant specs in more detail. It seems the phone has the same Sony IMX shooters as some older Pixels on its front and back.
https://www.notebookcheck.net/The-Pixel-4a-s-full-camera-specs-are-allegedly-detailed-in-a-new-leak.463699.0.html