“Guys” can be used in English as gender neutral to refer to a group of mixed gender.

You will even hear women refer to other women as “guys.”

The closest linguistic equivalent with a feminine tilt would be “gals.” “Guys and gals” is a rather informal variant of “ladies and gentlemen.” (Note the reverse order.)

Edit: As noted by @kitukwfyer in the question comments, it is possible for “gals” to be derogatory when used by itself so be careful. It’s not likely to be a problem used in the pairing above. Used carefully it’s probably safe, but used by itself it could be heard as mockery.

Saying the following is unlikely to offend anyone:

“The gals talked in the kitchen while the guys went out to see Fred’s new truck.”

But walking up to a couple women on a street corner and saying this might get a strange reaction:

“Excuse me gals, where is the grocery store?”

Saying this to a couple girls might make them doubt you:

“Hey gals come with me.”

But if you are explaining some game instructions and say the following it’s likely to be fine:

“Alright, guys on this side of the room, gals on the other.”

First of all, this is absolutely a usage that is particularly notable within LGBT and social justice communities, and there is definitely some sort of gender connotation. People who do not spend a lot of time in these communities may not be familiar with it. While "folks" may be on the rise in general, it is disproportionately so in these specific contexts. The "folks" phenomenon comes up often in internet parody.

My personal speculation is that this usage originated with demographically descriptive adjectives ("trans folk/s", "black folk/s") for a couple of reasons. Some phrases, even though absolutely neutral, with demographical references in them, have become latently politically charged in the eyes of out-groups even though there is no specific connotation (such as "black people"). I think the use of "folk/s" is to avoid that phenomenon. In fact, this also allows the speaker to avoid saying something like "these people" referring to a set of specific people, accidentally sounding like they are referring to the entire class the person is in (even though "folks" isn't any more specific than "people" in this regard-- "persons" is rarely used in speech-- there is not going to be the hair-trigger association that something like "these people" has). Also consider use in a greeting: "Hey people!" sounds blunt and almost aggressive to some. I'm not able to explain why, but I know that it can and does offend certain people. Almost like the speaker is a teacher yelling for people's attention. "Hey folks!" avoids this.