My experience is that the Costco exclusive models of many electronic products are not feature reduced but are identical to the non Costco versions except bundled with accessories or services not included with the non Costco versions.
For example Ring security systems and cameras sold at Costco usually include additional sensors or things such as additional Ring chimes plus a free year of service.
Back in the day, I haven't bought one in years and can't speak to the current situation, printers sold at Costco almost always had unique model numbers because Costco insisted printer manufacturers include USB cables and full ink or toner cartridges instead of starter ones. So if HP sold a model 420 everywhere else they would sell a model 425 at Costco which included the cable and full ink cartridges but the printer itself was identical to the 420 sold elsewhere.
A couple of years ago I bought an electronic keyboard for my daughter. It had a different model number than the keyboard normally has but the keyboard itself is the same feature wise as sold other places but it came bundled with a stand and a couple of other accessories which would have been extra elsewhere.