Further text from your link:
"The laptop still has room for a 2.5-inch storage device and a second NVMe SSD. Since our test device doesn't include the SATA slot necessary for the use of a 2.5-inch drive, the only option left is to install a second NVMe SSD. SSDs in the M.2 2230 and M.2 2280 formats can be used. The use of the latter requires the 2.5-inch drive frame to be removed and the retaining screw to be relocated afterwards (see pictures). "
The small space circled in Red is not even 2242, but rather 2230. (I thought it looked a bit short for 42)
You can have 2x storage devices.
1x HDD + 1 2280
1x HDD + 1x 2230
1x 2280 + 1x 2280, IF and only IF you remove the HDD drive bay.