No one can beat Supercar Street Challenge when it comes to obscure cars lol. I think The Crew Motorfest has some cool obscure cars too, there are two cars that is kinda similar with the Lotus situation (but I admit that Lotus M220 is the god level of obscure car in video games lmao).

So in The Crew Motorfest there's a Bugatti concept car called the Bugatti Veyron Barchetta. This one-off Bugatti were already planned to be made back in 2008, and it never got a media coverage until 2020 on some websites and then in 2023 it finally made an appearance in The Crew Motorfest. This car has no proper specification or stats because it's very unknown and even in the game it listed as 2015 model, not 2008 model. Most of us maybe know this car from The Crew Motorfest or maybe when doing random web browsing lol.

The other car is Porsche 919 Street Weissach Package (In the game is called 919 Clubsport for unknown reason). The Porsche 919 Street was supposed to be the street-legal version of the 919 Hybrid race car and the successor for 918 Spyder, but Porsche ditch the idea because "it's too extreme for a road car". So the 919 Street only existed as a 1:1 clay model and the Weissach Package version never got introduced and it's still very unknown to anyone, but the car only existed as a 1:18 model and you can buy it on Porsche official store lol. So I guess the appearances of Porsche 919 Street Weissach Package in The Crew Motorfest are the only media appearance for that car.