Accordint to the recent change in NNBD specification
Let L be a library that exports a declaration D named main. ... It is a compile-time error if D declares more than two required positional parameters, or if there are any required named parameters.
In fact, there are no issues in analyzer and runtime NoSuchMethodError in VM in both cases below
void main(List<String> args, var i, var j) {}
void main({required List<String> args}) {}
There must be a compile error in both analyzer and CFE
Dart SDK version: 2.10.0-110.0.dev (dev) (Wed Sep 9 17:51:43 2020 -0700) on "windows_x64"