Short answer: yes. DC is a comic book company in the Marvel universe. Foggy could have totally read Supes or Batman comics.
Long asnwer, also a personal headcanon: I like to think that all the Marvel properties that don't fall under the MCU - so the X-Men, for example - also exist as comic books in the MCU. I find it funny to have MCU characters discuss X-Men or FF. I can see Foggy being all excited for the Deadpool movie.
Foggy and Matt could have also read Captain America comics. It's MCU canon that Steve had comics written about him.
Re: this is probably the dumbest + most confusing question
Long asnwer, also a personal headcanon: I like to think that all the Marvel properties that don't fall under the MCU - so the X-Men, for example - also exist as comic books in the MCU. I find it funny to have MCU characters discuss X-Men or FF. I can see Foggy being all excited for the Deadpool movie.
Foggy and Matt could have also read Captain America comics. It's MCU canon that Steve had comics written about him.