No, you cannot play Dying Light 2 after the epilogue. Once you reach the end of the game, that's it - your journey is over. Some people have theorized that there may be some sort of secret ending or post-credits scene that tease a sequel, but as of right now, there is no confirmation of anything like that. If you're looking for more Dying Light content, you'll have to either replay the game or wait for the DLC to release.