Female plants produce the chemical ethylene, which is also responsible for fruit ripening. Ethylene inhibits the formation of male flowering parts (pollen sacs).
Silver-containing sprays such as silver thiosulfate and colloidal silver suspensions inhibit the production of ethylene, which allows male flowering parts to grow.
Because female plants do not carry a male sex chromosome, they can produce pollen from those sacs, but that pollen cannot carry a male chromosome because the plant it came from doesn’t have one.
When you pollinate another female plant with that pollen, the offspring should all be female because neither plant has a male sex chromosome to pass on to the offspring. This is the origin of feminized seed.