So I borrowed a Darkglass B3K from my band's bass player to try and recreate it with the Axe-Fx. I didn't use tone matching or match EQ since I know people don't want that. I don't want that. So I "ear matched" and "measure matched" a Drive block and PEQ block until I got something that was inaudibly close. The low end is always a bit hard for bass since it depends on how hard you pick etc. but I think I got really close.
This is the highest gain setting you can get out of a B3K so the modes are BOOST and FAT with everything on full. So instead of using the MIX knob for blending the signal I advice you to run the drive and PEQ in parallel so the PEQ only affects the driven sound and not your raw bass sound. DRIVE should never go past 4.50 in the drive block.
Get the preset here: Axe-Change - Download Preset - ML Sound Lab B3K - by Clark Kent
Here are pics in case you have problems:
They make these pedals in Finland where I'm from by the way.
Clips and feedback please!