Throughout the many video games and three TV shows there was only one live-action Carmen Sandiego actress, from the TV version of Where In Time Is Carmen Sandiego, (The only game I actually own is the NES version of this one.) However, since the show wanted to play up the mystery the actress was never credited. Todd Van Luling of The Huffington Post got his ACME Detective’s license to track her down and he was successful. As a bonus he talked to Kevin Shinick (Lynne Thigpen, who played the Chief in both PBS game shows based on the game series, passed away in 2003) and learned more about her mystery portrayer and the other roles she did on the PBS game show.
Now find the voice actress from the other PBS Carmen game show, Where In The World Is Carmen Sandiego. The only portrayer I know is Rita Moreno from Where On Earth Is Carmen Sandiego, the DIC animated series from Fox Kids, who was also on the original version of The Electric Company and a few guest-star roles.