Certification was completed back in 2021 after conclusion of a FOGRA research project. The color exchange profile (ICC) can be downloaded from the FOGRA website.

In essence expanded (or extended, varies by publication) color gamut offset printing is the idea of increasing the color space of CMYK using 3 additional colors (orange, green, violet).

CMYKOGV as characterized by FOGRA 55 is proofable using Epson SureColor printers (P7570, P9570).

I have seen several printers already offering 7c offset print. These days it's basically to cut down on cost (to achieve almost complete Pantone coverage without having to resort to actually spot colors).

A first viable compatibility step would be for InDesign to export CMYKOGV in PDF/X-3/X-1a as 4C + spot color plates, since FOGRA 55 is based on FOGRA 51.

The obvious missing piece is for InDesign to actually support CMYKOGV, which in itself is going to be quite a journey as the color model is everything but intuitive.

Maybe the use of an exchange color space (CMYK or RGB) that maps 100% to the gamut of CMYKOGV and is only separated on export (or for separation preview) would be the way to implement that in a way that users will actually be able to deal with.

Right now I have a project, which would usually be done in offset printing given the scale, but for DTP color gamut reasons will probably have to be done in digital print. It's rare to have the issue that you have the technical means to get it printed, but lack the means to create the preprint files these days.

There are sketchy workarounds, such as providing preprint files where some objects are defined in RGB color spaces, then get it proofed using 7c target and hope that the printing shop will actually manage to convert the RGB objects into 7c the right way.