Austria’s Claw Gear exhibited two load carriage harnesses.
This minimalist rig consists of the 4 Point Harness Lightweight, Operators Sleeve, and Sleeve Belt LW.
For heavier loads consider the padded 4 Point Harness, Raider Sleeve, and Sleeve Belt.
Looks very similar to First Spear AGB Suspenders. I’m currently using the First Spear one and it’s simple and comfortable. Can’t go wrong with basic H-harness.