Reality has the Auto Assault-12 (AA-12) shotgun (originally designed and known as the Atchisson Assault Shotgun). The AA-12 can fire in semi-automatic or fully automatic mode at 300 rounds per minute (5 every second) and has a magazine of 32 rounds. The AA-12 can fire 120 grenade rounds per minute with 9 foot blast radius. Having one AA-12 in each hand doubles the rate of fire.
New electromagnetic pulse (EMP) grenades could be adapted to the AA-12 as well, that would emit hundreds of megawatts of EMP for microseconds. A small e-bomb will be qualitatively different than larger versions. Radiated power falls off with the square of distance, so a target 3 meters (10 ft.) away receives 100 times the effect of one 30 meters away. An EMP grenade would probably only be effective for a 10-30 foot radius.
Still four grenade rounds per second (one in each hand) would let one person to hold back an assault by people or robots across the width of a football field.
Nanotechnology could increase capacitor storage by 100 times or more. Superconductors could increase the strength of magnets many times. This could allow the EMP rounds to fit into the size of ordinary ammunition.
The super low recoil AA-12 can be placed onto cheap UAVs and robots. However, with the likely proliferation of EMP and high power microwave devices, any robot that will be operating on a future battlefield will need to be hardened against EMP.
Exoskeletons are also being deployed today. The higher density energy storage, improved engines and stronger and lighter materials will further enhance future exoskeletons. Again any future exoskeleton will need to be hardened against EMP.