Skins are alternate designs for cars. They are currently unreleased, despite being first announced in 2013. The majority of skins are accessible in the Nitro Type source code. If skins are ever released, it is unclear how they will work or how they will be obtained. In the past, they have talked about how skins would be obtainable by racing with a certain car enough times to "level it up" and obtain its skin , or buying the skin directly from the Dealership. On the Nitro Type Discord server, Travis shared a gif that suggested that skins would be able to be selected when painting a car. However, skins of cars have been released as "variants" in seasons and in the Shop.
Because of how long ago it was first hinted at, many players have shown their disdain for the developers not keeping to their word. Other players do not even want skins to be released both due to their thinking that skins already technically exist in the game (as seen in event car variants) or their opinions that cars are already satisfactory with their current designs.
These are examples of cars that were released as a "reskin" or a variant of a previously released car. There are many that look the same with a similar size which can be found around Nitro Type. Many could be obtained in different seasons, or in the dealership for a reasonable price in a short period of time. They can also be re-released in the shop.