Ah ok.
I know 4-5-1 as a formation used to keep more possession of the ball and also is strong in defence with 10 men behind the ball (2 defensive lines, 4 players and 5 players). It was a formation that was used during some periods by certain teams for European competitions like the Champions League; it was like the formation that would provide more safety for two-legged situations.
In this game, it is a rare formation, that is, it is rarely used. But I came across a few of those since I started playing this game. I have been thinking of using it for certain situations.
BTW, 4-5-1 Flat can beat 4-5-1(V) (or could if it no longer can these days).