The only problem with the [Kuva Sobek] is the lack of AoE damage outside of [Acid Shells]. We fix this by going for an Electricity build and progenitor.

[Acid Shells] makes the weapon really good at handling groups expecially when combined with some game mechanics. [Shotgun Elementalist], Roar, [Xata]'s Whisper and Toxic Lash affect the explosion from [Acid Shells], so find the best way to implement those conditions in your build. Faction damage is easily findable but you have to build the weapon according to it, or just go Roar. [Saryn] can have both [Xata]'s and Toxic Lash. [Xata]'s is a generally good subsume and it works absolutely wonders on [Zephyr]'s Tornado alongside [Acid Shells] (you should try it, Tornado has some incredible math behind).

[Jade] Shadows' update brought a new era of damage and status: Electricity was greatly buffed in this update because it lost every negative damage modifier it previously had (like a lot other damage types). We also want to lean into Electricity mods since the status effect scales on Electricity damage.

The Electricity status effect can headshot even though it has a 1x Headshot multiplier. We can increase that by using Primary Deadhead, which also reduces our Recoil. An Electricity proc on the head benefits twice from the Headshot multiplier, because it's applied to the damage itself and to the status effect (so instead of 1.3x it's 1.69x, nice). Same applies for Gas if you want to build into it.

I went for a Crit build because the [Kuva Sobek] has decent crit stats, and they also make Electricity and Slash procs better. This pretty much requires to have a Companion setup that allows Reinfoced Bond though, which is something I'd suggest doing to everyone anyway. This is because the [Sobek] actually requires the fire rate and the only good crit mod for Shotguns is [Critical Deceleration]. The alternative is running [Shotgun Barrage], but it's hard to find the space and you always need the Fire Rate anyway so might as well invest on the [Reinforced Bond] setup in my humble opinion.

[Clip Delegation] is an awesome mod. The sheer amount of status and multishot, combined, makes that you will proc tons and tons of Electricity status for every shot. Give it a try!

BONUS GAS BUILD

The best alternative to crit would be capitalizing on status effects and run Gas instead of Crit. Run [Blaze] (or [Scattering Inferno]) and [Toxic Barrage]. This way it has even better aoe (with less Electricity procs though). At this point you can also drop [Galvanized Savvy] so you can either run a faction mod or [Shotgun Barrage]. Again, [Reinforced Bond] setups are still highly suggested since faction damage double dips on status effects.

TLDR: replace crit mods with [Blaze] and [Toxic Barrage]. Probably replace [Galvanized Savvy] with faction damage or fire rate if no other alternative is found.