With Shotgun Savvy, this bonus can be increased to 330%. Best use might be the kuva weapons from the. For example, a Strun with a max rank Shell Shock and Shotgun Savvy will have a 20% × (1 + 60% + 90%) = 50% status chance.
Some of these mods affect both those stats beneficially, while others increase one stat in exchange for decreasing the other stat.
Baro Ki'Teer -1 Shell Shock is a mod that increases both the Electricity damage and status chance of a shotgun by 15% per rank for a maximum of 60% at rank 3.