You will see straightaway that the QR codes on the Prestige book stamps are quite different from the sheets issues. For a moment, I thought this would enable us to distinguish one from the other. But no, of course, as each individual stamp will have a different QR code and that will not help after all!
I suppose it is feasible that part of the design might remain constant to reflect the common source but I would need someone to advise me on that one. There will be something in the long string of characters that will be produced but identifying that amongst the mass of white squares is not something I am going to attempt without guidance!
The slight difference in size of the issues here is purely down to my inconsistent cropping of the later images. Apologies. The colour difference should also be ignored.
Update 16 June 2022
I am grateful to Lew Paterson for looking at the QR codes for these (and some other) issues. Here are his findings.
The 4 codes for these illustrations are:
JGB S19981017031001847760010025012201 F6B51D5D00FE2D5801
JGB S19941017031004573840010012012201 7A2413CCC098BDEB01
JGB S19981017031000997760005024012201 53FAA4B2899ACD6801
JGB S19941017031005321590005011012201 D1E0328AE6EDE24501
Possibly the first of each pair, has S1998 while the second has S1994 - could these be different source codes? Yep, just tried my own - S1998 is the Prestige sheet while S1994 is the counter sheets
Looking further, the counter, Book of 8, book of 4 and business stamps use S11 for normal stamps and S12 for large stamps with the last 2 digits in the 20s for 2nd class and in the 10s for 1st class.