How to get into a specialization

Full-stack dev with 5yoe and no degree based in NL. I'm honestly quite bored of React, .NET and web dev in general. Looking for advice to get into some more niche languages/fields that still have job prospects.

I feel like most of these fields like AI/ML or embedded require a degree, are there any that someone without a degree could get into? Or maybe some more niche languages like Rust. How doable do you think this is, and how long would it take?