I think your quite hireable. Working on your own startup for so long must have diversified your skills. Your profile could very well be suitable for a product or an engineering manager role. As you can wear multiple hats.

31 is an awesome age - don't worry too much about that.

Since you have been shipping real products, adding them to your portfolio would add a lot of value.

There are also ample remote oppertunitues nowadays. Here is a curated list of remote job boards -

Recommended

https://news.ycombinator.com/jobs

https://www.producthunt.com/jobs?remote_ok=true

https://www.producthunt.com/jobs

https://remoteok.io/

https://weworkremotely.com/

https://remote.com/

Others

https://codefund.io/jobs

https://www.remotejob.rocks/

https://www.remotelyawesomejobs.com/

https://www.flexjobs.com/

https://www.workingnomads.co/

https://remotive.io/

https://www.skipthedrive.com/

https://www.remotey.com/

https://angel.co/jobs

https://remotehub.io/

https://remoters.net/jobs/

https://wellpaid.io/

Good luck!