Two Zero Zero One Colon Delta Bravo Eight Colon Eight Five Alpha Three Colon (pause) Colon Eight Alpha Two Echo Colon Three Seven Zero Colon Seven Three Three Four.
The part in the middle might need a better way of announcing, but given the double digits in other parts of the address it seems more natural to read it as a string of characters than to alter it.
For a mac address I'd not summarize and just read it off in 6 pairs.
For the example representation address on the wikipedia page... 2001:0db8:85a3:0000:0000:8a2e:0370:7334 ( https://en.wikipedia.org/wiki/IPv6_address )
Two Zero Zero One Colon Delta Bravo Eight Colon Eight Five Alpha Three Colon (pause) Colon Eight Alpha Two Echo Colon Three Seven Zero Colon Seven Three Three Four.
The part in the middle might need a better way of announcing, but given the double digits in other parts of the address it seems more natural to read it as a string of characters than to alter it.