With firmware v3.0 on the X-PRO2 and v2.0 on the X-T2, Fuji announced that ISO L would provide ISO 125 and ISO 160 as selectable.

It doesn’t always work. BTW, the same thing also happens with the ISO 25600 or ISO 51200 of the ISO HIGH.

This is due to the fact that ISO HIGH or ISO LOW does not work if the Electronic Shutter (ES) is enabled. It could be either as Electronic Shutter only or Mechanical Shutter + Electronic Shutter (MS+ES).