I have seen a related question here, but the answer didn't cover how to sort them by upload date.
Is there any extension/website capable of doing this?
Related question: Play all YouTube videos uploaded by one user
This site offers shuffle and reverse: YouTube Jukebox
Videos are sorted by date decremeting by default.
Go to playbackloop.com and you can paste in a YouTube playlist or channel URL and it will play it in chronological order.
It uses the YouTube API and works great. It looks like they only play in order from oldest to newest though.
I think there is a good reason why it was not covered, because the sort-by-date filter is right there -
Visit the user's channel(My Channel), click on "Videos" and you can see the filter on right hand side.
Before YouTube was bought by Google the ability to reverse the playlist existed. It has since been removed. It is not some forgotten feature, not to mention its a very obvious feature that people have been asking about for a very long time. This is annoying. I want to watch the Starcraft Pro League and not see the names of who's playing who, so I don't get any spoilers, and I want to watch it in order... But no, Google/YouTube has to be jerks about it.
There's an extension in Chrome called Reverse YouTube Playlist, but entering its name into the extension search doesn't bring it up. However, it can be found using a web search engine, like Google, possibly Bing, Yahoo, or something.