Flatout 4 is possible for the Nintendo Switch according to Susan Cummings from Strategy first who said the following
It’s certainly possible. It’s definitely something Strategy First have been watching with interest – the early success of the Switch. I wouldn’t say anything is out of the question.
The Switch version can be made if the system continues to sell well and the community shows interest in the games that are released for the system. Time will tell if this game will reach the switch and until then we will wait