Here you go. This is somewhat simplistic - spawn your weapon however you are spawning it, I just did mine as an example.
Then in your pickup blueprint or whatever it is you are overlapping put this:
In my “Weapon” blueprint I have the variable float “RoundsPerSecond” which I can then draw from the instance reference I set from the player character that I set when I spawned the weapon.
Hope this helps! If so, please consider accepting the answer by clicking the check mark located under the arrows next to the answer! Thanks and good luck!