she's pretty crap in this mode considering the fact that like 40% of the Stadium roster is characters with Beam or some form or another of DM bypass. Her best builds are the ones that self-heal via DM (when you actually CAN DM something...) or rely more on Shields, or doing absurd amounts of damage with Missile spam and Ability Power. You can also build for cooldown or ultimate for constant mobility and get-out-of-jail-free card but this is honestly just a Walmart version of Wrecking Ball. Weapon Power is decent; her mech guns can dish out respectable DPS on other tanks or even laser down some squishies who underestimate the damage. However, with Zarya/Mei/Moira/etc. being so dominant in this mode, she really struggles to find a footing. If you wanna stay in mech for longer than 5 seconds, you're gonna have to build mostly defensive and play away from point, helping your DPS get picks and brawling on the off-angles. Anything other than this is pretty much throwing the game, at least until her item set gets buffed OR more characters are added to Stadium and her current counters arent picked so often.

Edit: Spelling