I played the scotch for a while, and i never saw Qf6. However, the line Qh4 is sometimes played, with if Nxc6 Qxe4+, with the kight on prix. With Nc3 there are lines with Bb4 and Ndb5, with many complications
I thought it was this line.
after the move 4...Qf6 I had success with 5.Nb3 preventing the dark-squared Bishop coming out to c5.