This is a quote from the show between Dr. Rodney McKay and Dr. Radek Zelenka attempted to theorize what would happen if a craft like a fighter left a hyperspace bubble while in flight, McKay expected that the craft would be destroyed while Zelenka proposed that it would be able to maneuver inside the hyperspace bubble.
I believe they are both right, although with a few factors to consider, as an hyperspace window is technically in another dimension, the show refers to it as another frequency but it makes more sense that it's another dimension as it is completely invulnerable to attack and track except with the more advanced races such as the alteran and the asgard.
While a ship is in hyperspace or subspace, it can pass through solid objects, such as planets or any other floating debris, which also means it could also bypass something like shields,
My theory is that an object can detach from a space craft while in an hyperspace window and all it would need is to, already be going that speed while being attached to the craft that is already in hyperspace, this allows for the object to have some level of protection but the object in question must stay within the bubble of the window and have it's shields active while in the hyperspace window as hyperspace is highly radioactive and can destroy the drone within seconds being exposed to the window.
however we know that the gould Anubis used an hyperspace window to transport an rock in tow and on the trajectory of earth, Anubis did this to make it look like an natural disaster to fool the asgard into not intervene as it looked like it was due to natural causes instead of an gould attack, this was an statement that the asgard went by when it came to the gould attacking their allies.
But Anubis's plan was thwarted as Sam exhausting all other options thought about opening an wormhole while closely towing the massive asteroid straight through the earth as she understood how the hyperspace window worked.
We also learn from another episode of stargate where Sam comes up with a brilliant idea to use the hyperspace window to destroy an replicator ship that was gaining on thor's remote controlled spaceship, Sam convinced thor to sacrifice that ship to the replicators except to blow it up in their face, and this method destroyed the replicator ship as it was most vulnerable within the hyperspace window.
Suffice to say, it is indeed possible to attack another ship while in hyperspace, however it's also possible to destroy a ship in tow as well, if an hyperspace window is opened up when not close enough to another object or ship, it can also tear an object to pieces by not being close enough to the ship that is towing it in.
I came to this conclusion through observing the Destiny's FTL drive when the drone ships were engaged in battle with Destiny, were close enough to attack but to close to avoid the Destiny from tearing them to shreds when Destiny's FTL drive engaged, effectively shredding the drone ships into pieces which might be another reason why the alien species kept their main control spaceship at an distance from destiny.
Now i know that FTL is slightly different from hyperspace, FTL is much slower but it's still invulnerable to solid objects outside it's hull while traveling within the FTL window, like traveling through an hyperspace window it can also tow objects, however with Destiny it seems like the ship that is in tow must be connected to the destiny in order for this to work, because there was an drone ship that was attached to the hull of the Destiny, and detached while Destiny was already engaged within FTL travel and this ship was able to resume roughly at the same speeds as Destiny but because this drone didn't have the capability of an FTL drive, it couldn't keep up with the FTL speeds and slowed down when it detached from the Destiny, and my assumption is the drone stayed within the FTL bubble until it was slow enough to travel without being in the bubble of the FTL travel stream before it could travel independently, however i think i remember it leaving the bubble before this happened, and the drone ship also had it's shields on while it left the FTL bubble. but i could be mistaken.
So gathering all this information on FTL and hyperspace travel, i do think it's possible to use weapons in hyperspace and FTL but it's indeed rarely ever used or seen in the show.
This information was thought up for my idea of using hyperspace windows as an indirect weapon that would be reusable given the right circumstances set in place.... if you want to read more on that concept i will leave the link right here if you are interested.
https://stargate.fandom.com/f/p/4400000000000149748
