Duel wield bloodhound fang

Hey I recently started a dual bloodhound fang build. I just got my second bloodhound fang and I noticed when I do bloodhound finesse it only swings one sword and puts the other one on my back. All the videos I watch, which are 3+ years old, they’re able to use both swords using bloodhound finesse. Has this been patched or am I doing something wrong? One thing to note is I have not upgraded the second weapon yet and my other one is plus 10. Thank you.