I must say, I don't see how any of the entries could have a very positive connotation, unless you're on the same team and underhanded / sneaky methods meet with your approval.
In my experience, gamesmanship always has a negative tinge, even though it's sometimes expected or necessary. It means knowing the rules so well that you can use them to your advantage, even if that isn't in keeping with gentlemanly behavior, chivalry, ethics, etc.
Examples of gamesmanship in soccer would be ...
• diving, exaggerating a hit
• writhing in apparent agony and clutching a body part in order to prompt a video replay
• committing a professional foul (taking a yellow card for the team)
• surreptitiously moving the ball forward from where it went out or where the foul occurred
• playing on until the whistle, even when an opponent may seem to be down injured
• protesting every call loudly, arguing with the referee, gesturing for VAR
• wasting time, running out the clock, especially near the end of the game