The Blair Witch Project x Scooby-Doo (1999)

Here's a gem from 1999: This is a self-aware Scooby-Doo-themed parody of the popular low-budget "found footage" horror flick, The Blair Witch Project.

It's called The Scooby-Doo Project and those meddling kids at Cartoon Network got away with it too.

In 2016, Paste reported this:

The Scooby-Doo Project. The odds are good that, even if you are a huge Adult Swim fan, you are hearing about this for the first time. It aired, it would seem, one day only, on Halloween in 1999. The special debuted in chunks spread out during commercial breaks of a Scooby-Doo marathon, before airing in its entirety at the end of the marathon. And yet, in spite of these humble beginnings, what we have in The Scooby-Doo Project is essentially an Adult Swim show that aired two years before Adult Swim debuted.

Scooby Doo would eventually feature in the Adult Swim lineup, when the gang appeared in an episode of Harvey Birdman. The joke was that Scooby and crew were arrested for marijuana possession, and were being defended by Harvey. The plot, of course, is based on a longstanding joke that presupposes these kids and their dog were bigtime stoners.

Another project that came out in 1999 was The Blair Witch Project, so you probably know by now where this whole thing is going. Blair Witch was a huge cultural phenomenon when it came out, but it has largely been forgotten now. Still, the film was important and influential in its own way, because it was a super cheap found footage horror movie that turned a huge profit. It was made for a mere $60,000, and grossed almost $250 million. The film was marketed really well, using the found footage style to promote itself like it was a documentary. The whole campaign attempted to lead people into believing these characters were real people, who had really disappeared under mysterious circumstances, related to the Blair Witch.

...Parodies of The Blair Witch Project were rampant at the time. There was a full movie called The Bogus Witch Project. The WWE had a parody called The Blonde Bytch Project that was so spectacularly ill-conceived they gave it the axe before finishing it up. And then there is The Scooby-Doo Projecta found footage short about the Scooby-Doo gang piling in the Mystery Machine to look for the Blair Witch.

(reddit)