I've made so many fanny pack prototypes and wasn't happy with the direction for any of them. And then, as usual, I went into the workshop and cut leather, went to the machine and made this in a few hours.
A simple pouch shape with very discreet d-rings appointed on each side, corresponding to a detachable strap. The strap can be shortened or lengthened to be either a waist pack or a cross body, as shown in the images provided. Exterior zip pocket for quick access to things that you need to get at fast.
Some things don't need to be complicated.
Front panel in ponyskin, back panel in veg tan. Strap in veg tan. Lined in cotton canvas with a small phone pocket inside.