Comment by eqvinox

It's impossible for this to interoperate with "normal" fiber, this is "coupled-core" fiber: the cores don't operate independently and a MIMO style setup like the paper describes is really the only thing you can do.

Additionally, the setup uses optical amplifiers in 86.1km steps.

Both of these things put this squarely in submarine-cable-only space. Total cable size is in fact a problem in that space, 4-core claddings are roughly state of the art there, but there's enough room for those to be non-coupled. Higher core counts requires research like this.

Either way you'd be terminating a 19-core setup like this with an OEO (and probably FlexE and/or an OTN solution) both ends.