GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
G:=Group((1,2)(3,4),(1,3)); F:=FreeGroup(2); F:=F/[F.1^2,F.2^2,(F.1*F.2)^4]; m2 := [[[0,1],[1,0]], [[1,0],[0,1]]]*Z(2);