Free Agent is not a type of player.

Players who are free agents can have just as many different characteristics as other transfer listed players. Fast, slow, good, bad - the only constant with Free agents is that their market value will be higher than the fee (not counting tokens) you pay for them.

Thats one of the reasons why, particularly at lower levels, some managers fight over high value free agents - for their re-sale value, as well as their performance value.