So I have a lot to say on this particular topic.
First things first, what everyone above has said, rest is essential. You've worked yourself to exhaustion on a project, and the burnout there hits hard. To poorly paraphrase something I've read online, creating and consuming art is like breathing out and breathing in. When you create, you're pushing energy out of yourself, and when you consume art, you're refilling that energy. If you've been exerting energy for a long time, you need time to refill it. Go do things that will refill you. Read some books, watch some movies, play some games, try art that you're unfamiliar with that won't feel like work anymore (cooking, knitting, painting, collage, sculpting, who knows), go for long walks and breathe some fresh air if you safely can, see some things you've never seen before, etc. etc.
I got very badly burned out on a project that I had worked on for years as well, and it almost felt like part of me had died when I realized that I needed to drop it. I won't say that the experience was identical to yours, but I know what it feels like to pour all of yourself into one project that almost starts to feel like an extension of yourself. I wanted my project to be perfect in every sense of the word, and I wanted it to be loved by everyone who read it. That goal was impossible from the start, and eventually led me to failure.
In my case, I wound up taking a break from creating for several months until ideas for other things started to flow again, eventually leading me back to "Redux". (A lot of people have said this in the past, but my creativity only came back once I wasn't looking for it anymore. It's funny how that works.)
In my case, moving from a very serious project to one that's sillier and gave me more freedom helped me a lot. I've given myself LOTS of room for imperfection and growth. I expect people to find flaws with it, and that's okay. I honestly couldn't be happier with the process right now, despite (and maybe even because of!) all of my little imperfections and flaws. It's a project that's undeniably mine. Perhaps something like that will work for you as well, and perhaps not.
Second, also to agree with what's already been said, you've been asking for advice on almost every step of this project. There's nothing wrong with asking for help, but it almost seems like you don't trust yourself to make decisions. If you choose to continue creating, it might be wise to take a step back and figure out why that's the case. These are your characters, your worlds, your stories. Not every decision we make in our work will be the "best one", but they will be your decisions. For better or worse, your decisions are what make it something that only you could have created. That's part of the game and part of the process.
You're the expert on what you need, and you're the only person who can really say what's best for your future projects. Have a little faith in yourself!
If or when the creative juices start flowing again, I look forward to seeing what you come up with! In the meantime, take care, have fun, and get lots of rest.