The Eight of swords is a part of the King of Swords so the King's qualities can be added to the interpretation.
The Eight of Swords temporarily stores ideas, taught by the Ten of Swords, for rapid retrieval for the purpose of further processing and studying the concept.
The Eight of Swords has a limited ability to reach conclusions and think.
The figure in various decks appears in blindfolds because it's not his job to think and draw conclusions, he works blindly. He serves as a storehouse and keeper of thoughts and conclusions not fully processed by the Ten of Swords.
It can be understood that these are thoughts and ideas that have not yet been born and are still in process and ripening.
As a person, he does not talk much or share his opinions.
He would prefer to stay away and shut himself off.