It's been a while since I did the Repairing the Phial quest on this playthrough, and just noticed I still had Briar Hearts in my inventory but they never showed up for alchemy. When I tried to mix them, they didn't show up as an option. I tried giving them to my follower or dropping them but I kept getting the quest item error. I saw this was fixed in 1.9.28 and I have version 1.9.32, so it seems like this shouldn't be an issue, but it is. Is there any console command to reset or delete them? Thanks!

The bug is in all similar items that also become quest items. The Amulets of Talos, for example. Im pretty sure the Unofficial Patch gets rid of them, but yeah theres a way to do it with the console:

So in your case, you would type "player.removeitem 0003ad61 1" without quotes. replace that last 1 with the number of briar hearts in your inventory.