Hey there.
Use the same link you specified,
https://support.hpe.com/hpesc/public/docDisplay?docId=a00028947en_us
or find the link on our Aruba Support Portal (ASP) (click on "Software & Documents, then Switches) and then search for "Transceiver Guide". There's both an HTML and PDF versions of the guide.
It'll be the same URL for all of our updates to the "ArubaOS-Switch and ArubaOS-CX Transceiver Guide".
As of May, 2020, it's now at Edition 8 (back in March when you looked it was indeed only at Edition 7 and didn't include as much about the 6300/6400 -- Edition 8 corrects that).
To answer your question more directly; read the Overview chapter, specifically page 13 about 4x4 part numbers.
Older xcvrs that were fine to use on our older switches, for the most part will work on 6300/6400 CX switches -- but...
Since many of the parts are old, we've concentrated on certifying newer xcvrs against our new switch series.
For example:
J4858C/J4858D 1G SX transceivers with 4x4 #s:
1990-4395 or 1990-4415 were certified and supported.
Over the years, we've retired four(4) other 4x4 #s, and those were just not certified (again, they may work... but just not for certain).
Some older vendor parts just plain didn't work properly -- eg. 10G LR on our 8325 25G Switch. When you see the listing of support for the specific xcvr you're interested in, look to see if there are specific 4x4s that we've absolutely tested and will STAND behind as 'supported'. Older parts that work -- well, they probably work -- but we haven't absolutely certified that older generation to work in all conditions. Examples of what we certify are not only operation, but hot-swapping the xcvr, continuing to work across reboots, work at max temperature (typically 45C).
Don't assume ANY or ALL will work -- they may, they may not. What you CAN count on are the ones we sell today, and any specific 4x4s we had to call out for full support - without question - and our full support to ensure they continue to work.
=Ed Kurata, Product Line Manager, Switching Accessories.