Currently, there is no option to jettison rocket pods once fully expended, even though they can be jettisoned when they still have rockets in them. Surely this doesn’t make any sense, considering the substantial drag they exert on the airframe for the rest of the match. The fix would be simple; jettisoning empty rocket pods automatically, similar to missile pylons. Considering the jettison mechanic is already implemented, this should be fairly simple.
There already is iirc, there is an option in the settings called “automatic jettisoning of expended weaponry” or something similar and will jettision rocket pods, bomb racks and missile adapters once they are fully expended
Does it work on the Hs 129?:
From what i remember, no its maily for higher tier aircraft like jets where its an integral part of the systems, iirc the lowest BR aircraft that has it right now is the new strikemaster in the battlepass at 6.3
If the Hs-129 has it though im sure you could make a bug report or suggestion to get it implemented, its always those little features that make certain aircraft stand out anyway