Essentially a PF30 with 86.5mm wide shell. Developed by FSA The bearings are internal, as opposed to outboard. 6806 Bearings are 46 outer, 30 inner and 7mm in width.
The Bikeradar guide says BB386 EVO was introduced in 2011 and takes the oversized principle to extremes. The shell width is still 86/92mm but has a 30mm spindle. I note that 86mm is considerably wider than 68mm. Note that it is not OSBB
Summary of BB386 EVO
Shell inner diameter 46mm
Bearing Inner diameter 30mm
BB Shell Width: 86.5 mm road
Installation: 6806 bearings in cups
The 2019 Specialized had a 86.5 This is the spec that the guy at Praxis thought the bike probably had. If your BB shell width is 86.5mm, then you have a 386EVO BB shell. This would likely be true if your Diverge is carbon. Here is the BB you need to install that crank if your BB shell is 386EVO: https://shop.gwbicycle.com/products/praxis-m30-bottom-bracket-386evo?variant=28654765146205
The Praxis M30 Bottom Bracket - 386 EVO would be one adapter. It has 30mm Drive bearing /28mm NonDrive bearing (cartridge bearings) $69.00 USD
Hambini says this is direct fit.