They indeed can play games while on the transfer list.
However be cautious when it is about Play Off games.
I'm not sure if it was a bug, and if it is fixed yet, or if it is intended that way, but I recall putting my center up for sale 3 seasons ago during the play-offs and as long as he was listed, I couldn't field him in a PO game. I think it has to do with the transfer deadline for players able to play in the POs...
In any regualr games or cup games, there should be no problem.
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