Both of these schools are in nice neighborhoods but they are pretty different! Brunswick is a small town. The nearest city is Portland. Swarthmore is a suburb of Philadelphia, which is a major city. This matters not just in terms of campus culture but in what’s available nearby. Philadelphia is much more diverse and multicultural which may impact how excited/comfortable you are about being off campus. It also changes what will be available to you and your friends if you leave campus for activities (and potentially the cost of it.)
Bowdoin is generally more social. While there are understand students who study on Friday night, that is likely to be more "normal " at Swat. That doesn’t mean you won’t find parties at Swat, but the overall pulse is different.
I believe both are committed to being inclusive. I’d definitely inquire about accessibility to events with FA. My recollection is that the Tri-Co schools do not have admission fees to anything on campus so that everything is available to everyone and there’s no hassle or stigma to getting free tickets. If you can attend revisits, this is something to poke around at at both. (Even virtually, you should be able to connect with some current students whose profile is similar to yours.,)
Overall both are excellent schools with great post grad prospects. You may want to look at your expected course of study, paying attention to what is required for your major as well as any distribution requirements as well as how you might fit in other things, like study abroad, etc.
Often, schools have somewhat different approaches to this. It’s rarely make or break, but it could be a tie breaker for you.
In this decision, you may get a somewhat better fit at one, but it’d be impossible to make a bad decision. GL!