Like everyone else is saying: there only really are chromium (blink), firefox (gecko) and Safari (WebKit). All other functional modern browsers are based on those. It's best to stick to one of them or a well known fork and customized them to your liking.
You can get most of Safari through GNOME Web if you're on Linux. You can use various Firefox forks if you don't like Firefox itself.
That's about it, to be honest. Ladybird is being built but it's far from complete yet. You can use Lynx and friends if you want to give terminal only browsing a go. Servo is pretty complete but Mozilla dropped them and development had been affected.
IE, Edge, and Opera all used to have their own browser engine. Now we just have three engines left, two if you ignore the meagre 4% market share Firefox still maintains.