The only successful Player-Coach that comes to mind was Eric Cantona as player-manager of the France national beach soccer team after leaving Manchester United aged 30.
He won the 2004 Euro Championship, the 2005 FIFA Beach Soccer World Cup along with a number of top 4 places over his 15 years as player and/or coach.
The fact that there have been so few of them throughout history of sports shows that this is an exceptional, uncommon situation. A small number of athletes compared to the total. It requires that a single individual possess many qualities at the same time.
Bill Russell. Won 9 championships as a Boston Celtic under legendary coach Red Auerbach, and alongside Hall of Famers like Bob Cousy. Then became the coach and starting center for 3 more years and won two more championships.
Rinus Michels [1]. There are so many tho.
[1] https://en.wikipedia.org/wiki/Rinus_Michels
https://en.wikipedia.org/wiki/Pete_Rose
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Kenny Dalglish for Liverpool too, winning the double whilst a player-manager.
And kicking the goal in the final match that secured the Premiership. Definitely counts as being a "professional" league.