Arrow's Emily Bett Rickards answers a major fan question about Fecliity! Watch it above (at 8:28)!
Arrow has many many theories and debates surrounding it - a sign that he DC Comics superhero show has created its own substantive mythos. One of the biggest things that is often discussed about the show is the character of Felicity, the hacker turned Team Arrow tech expert - now turned hacker again?
Besides the raging fires of debate surrounding the "Olicity" romance between Felicity and Oliver Queen, another debate has been raging over whether or not Felicity actresss Emily Bett Rickards will ever suit up in costume as a superhero. As you can see above, Rickards has a pretty definitive answer to that particular question.
The long short of her answer is this: If Arrow (or any other Arrowverse show) finds a way to incorporate some alternate earth doppleganger version of Felicity who is a superhero? Then she'll suit up. However, the Earth One (or main continuity) Felicity we know and (most of us) love, will probably never be suiting up as a superhero.
That sentiment has also been echoed by Arrow ececutive producer Marc Guggenheim, who has previously stated that having Felicity suit up as a superhero is one of two things he would NEVER do on the show. In other words: this is one of those debates that fans can definitely put to rest, at this point.