I'm making a shoe bench in a similar style to the Nelson Platform Bench. Not that there aren't other differences in my design but the "real thing" has mitre-joined legs.
I went with a butt joint, all based around a 5° cut. It was easy to cut, and the main legs can transfer most of the load directly to the ground without forcing outward. More than anything this is a shoe bench, and a pretty low one at that. It's not actually going to get sat on much.
But having reached the assembly table, I'm now having doubts about how to assemble and affix and even possibly reinforce this.
My first thought was pocket screws from underneath the two horizontals, out into the legs. They won't be visible but the complicate attaching to the benchtop.
I could cut longer trusses (the horizontal bits; not sure what to call them) and make a mortice-tenon but that drastically complicates things, especially with the 5° angle.
Dowel/floating-tenon would work but again, it's more complicated than a pocket and I don't believe the a dowel here would see any of the sheering forces they're designed to resist. 90% of the force on this bench goes directly through the vertical legs.
So... Glue and pocket screws?
The timber is red grandis.