I can't remember if the AI Only naval aircraft have folding wings or not. If not, there's no way to change the visual model.

PS. I just tried it with the default Avenger. I copy/pasted the [folding_wings] Aircraft.cfg entry from a similar type, in this case the default Hellcat. You might like to add the [TailHook] entry too.

[folding_wings]
wing_fold_system_type = 4                  ;0=None
fold_rates = 0.12,0.13                        ;Percent per second