It’s a pity that the common annotation for a “surprising” move is to follow the move code with an examination mark (or two) rather than preceding it; otherwise we would have a simple way of making the model generate surprising moves on command. :)
> otherwise we would have a simple way of making the model generate surprising moves on command
One method would be to just take the 3rd or 4th best move option. It wouldn't be a winning strategy but it would probably be pretty surprising and still moderately effective.
Also, I'd imagine that the most surprising moves would require the opponent to make a very precise series of moves to avoid a losing position. While the best moves usually slowly improve your position, the most surprising moves might polarize the position by giving the opponent a chance to improve but also making the chance of a costly blunder more likely.
In that sense you could look for moves that give the opponent the fewest number of positive expected value moves rather than finding moves that give your opponent the lowest possible EV response.