I have a Merrill+ Visa Signature card and I was wondering if its possible to product change this to an Accolades Amex version?
Well, no...and no. If you mean like with other cards from other issuers, then the answer is likely a NO. The Accolades card is not offered on their website, and when it was, one could not apply on line, one had to call ML to make application by phone. From all appearances, it's been eliminated. However...
Apparently the Accolades has not been eliminated, just much more difficult to obtain. I called ML card services some time ago when I got my Merrill + card, they advised that it's still available, but one has to apply for it through your Merrill Lynch Broker/Advisor. So, it appears it's reverted back to having to have assets established with ML to even apply for it, rather than being open to general application. Guess that's why they took it off the ML website, that it's not generally available but is now even more of a specialty card. That was about a year ago that I talked to them, it's possible it's no longer available at all, given it's overall history.