Aluminum frame.

I thought there were quite a few 130mm disc Cross bikes. Perhaps those were rim brake bikes.

Here is the Bontrager SSR Disc Road Rear Wheel in 130 or 135mm, but only 24 spokes.

Will converting a 135mm hub to 130mm put the disc in the wrong place?

These Formula hubs are listed as 130mm, with either 32 or 36 spokes.
Formula Rear Disc QR cassette sealed 130mm Hub 32H Black / 36H silver