@Piggies12437392 might think piggy two is female, but I'm not sure it's possible to be certain from your photo. Please try looking within the slit and trying to press above the genitals to push the penis out for this piggy too.
You need to check for the presence/absence of a fleshy seal inside the slit. Or the presence/absence of the penis ridge above the slit. On a boar the slit goes straight down. On a sow there is the fleshy seal.
Use the @alpacasqueak linked to above. You can try posting clearer photos but it’s best to learn how to do it - hands on sexing is always the best way to go, rather than guesses on the internet.
Please accept that we do not play guessing games on here (and I would kindly ask any new members to please respect this).
The gender is often not quite clear just from the outside, especially not on fuzzy pictures or genitalia with coloured skin markings. We have seen guesses just from the outside appearance go wide off the mark in previous times to want to continue this.
The problem is also that you can never know just how experienced and therefore reliable the posters themselves actually are.
Prying into the slit and checking whether there is a a fleshy flap arrangement that seals the opening just below the rim (sows) or whether there is a straight slit going down (boars) is much more easier to spot. Feeling for the presence/absence of a tiny penis shaft under the skin just above the knob is an added safety measure. Because if both hands-on measures come back with the same answer, you can be 100% sure that you have got the correct sex. Expressing the penis is often not easy for new owners. Unfortunately we cannot do these hands-on checks for you but rest assured that we do them with every piggy we handle ourselves!
Personally I would think that learning how you can sex piggies by knowing where to look without having to rely on other people is not the worst life skill to acquire and that it is worth having a look at our sexing guide, which has plenty of reference pictures (including slit pictures) of piggies of different ages. And a nice big arrow in the first picture where to gently feel for the penis shaft!
Here is the link again: Illustrated Sexing Guide
If you still struggle after trying it our way, you are welcome to post clear pictures of the slit opening. You may need somebody else to hold your piggies or to take the picture for you. It much easier when you have somebody to help and also to their own assessment.