If there was a custom GeForce RTX 2080 Ti that I'm waiting for, it would be the MSI GeForce RTX 2080 Ti Lightning Z which has now been spotted - at least naked, so we get a good look at the PCB.
We are expecting MSI to unveil the new GeForce RTX 2080 Ti Lightning Z at CES 2019 in a few days time, with new HWBOT submissions teasing the card and its existence. There are two HWBOT entries with GPU clocks that exceed 2450MHz, which will be thanks to the monster RTX 2080 Ti Lightning Z and its 19-phase VRM and 3 x 8-pin PCIe power connectors.
There are multiple fan connectors and voltage connectors on the end of the card, with the entire end of the card cover ed in its own awesome heat plate that should keep that side of the card cool. This is a big deal for overclockers and enthusiasts, as there will be a LOT of power going into these cards when they're pushed to beyond their limits with LN2 cooling and the like.