Your CB90 isn't going to work via plug and play like that without major modifications to the stern to include a higher freeboard or an almost well deck like situation (impossible now as there is little to no underwater hull at the stern). The CB90 has an extra meter of beam, five more meters or length and probably another meter or so of height from keel to upper superstructure BEFORE adding in permanent sensor mounts over the SB90E that that those berths is designed to hold and service. Its also twice the displacement of the SB90E so your extendable gantry crane is going to need some serious beefing up.
Hmmm,
A enlarged stern doors & a
bigger gantry crane should do the job...
(from 6-9 tons for a SRC 90E to 17-22 tons for a CB 90HS)
Also those containers you have look small, are they standard intermodel? Even if they are they their number is almost not worth the effort as drawn, I think you could do some major reduction of the superstructure in that area given the weapon systems that were removed to make for a larger container capacity.
The middle space is wide enough to receive containers...
Absalon (large !) Flex Deck