Sounds like it could be more of a festival than a conference, so depending on how things are actually laid out, you could participate in some things whilst baby is in a sling.
"Specifically, we're aiming to dump the sexism that infests many geek spaces and sci-fi cons. We've got a strong anti-harassment policy and we'll work hard to make Nine Worlds a safe space for women, LGBT+ people, people with access issues, and other groups that are often marginalised at geek/fandom events."
I wonder if safe space for women also means they are providing baby changing facilities... probably not what they have in mind, though perhaps call the organisers and see what they say. As they want to encourage women, maybe they could do things to encourage mothers.
"At Nine Worlds you'll be able to wander from session to session"
But does that mean you can leave a session part way through when baby starts to make a noise?
"We're founded on the radical belief that geekdom should not be restricted by class, age, gender, sexuality, ethnicity, disability, or the ability to cite Wookieepedia in arguments."
So an age of 2 months should not be a problem then.
In the FAQ (on KickStarter) it says that children are welcome.
"We do not want to disadvantage or exclude people with childcare responsibilities, and are committed to making the convention a friendly and safe environment for children. Young children will get free entry, and we'll sell half price tickets for older children once the Kickstarter has finished. Children must be accompanied by adult parents or guardians, who are responsible for their safety and behaviour. We have appointed a child friendliness co-ordinator, who will help to bring together a range of age appropriate content throughout the convention and act as a point of contact for questions and concerns about these issues."
So, if you are sensible then I think it could go great. Perhaps get in touch with the child friendliness co-ordinator so that they know you are coming and thus what baby friendly things they may need to try to arrange, such as somewhere quite to feed baby.
When you are there, keep in mind about Heat level, Noise level and the general busyness of things, as you do not want you and baby to get pushed/shoved, or get too hot, too cold, of have babies sensitive hearing damaged.
Never been to anything like this myself with a young child. Sounds like it could be fun though. Many parents these days go to festivals with children, so why not try seeing if it would work for this convention/festival. The organisers seem up for it, so that's a good start.