Is there anywhere I can work on improving my Swedish accent? The only language I can do a convincing enough accent in while speaking is French, because it's the language I've been working on the longest, and I would like similar ability with Swedish. Are there any websites or courses I could do to help with this?
Any website where you can hear a native speaker talking should help. Films and TV/Radio programmes or Podcasts will help.
Also, Mango languages uses voice comparison for it's dialogues. I set my Google app to Swedish so when I say OK Google I have to speak in Swedish to get it to do what I want. It takes me a lot longer to use it because it is not very forgiving about bad accents at times.
Have you checked on italki? You can take one on one lessons with teachers. If your vocabulary, grammar and sentence structure are solid, you can ask a teacher to focus on adjusting your pronunciation to reach the level you want. This is the link for Swedish teachers https://www.italki.com/teachers/swedish