Complex sentence: Generally, this means players have played at least 50 matches or scored 10 goals for the club, but some players who have played fewer matches are included, if they have had success at other clubs or appeared at least once in the national team.
Split into simpler sentences: Generally, this means players have played at least 50 matches or scored 10 goals for the club. However, some players who have played fewer matches are included also, this includes players considerable that have had success at other clubs, in national and players who have appeared at least once in the national team.