Problem:

Can nozzle loads (weights) be added to the nozzles for the hydrotest case?

Solution:

It is not feasible to apply external loads on a nozzle during the hydrotest.
As a workaround,

You can save as the current model under the name 'XYZ'.
Adjust the design parameters to match the hydrotest conditions.
Then, incorporate the desired external local loads on the nozzle as shown in screenshot below.