After finishing the Modwyr quest, choosing to release her soul and keeping the sword, the new Modwyr appeared in the stash, however, the old Modwyr wasn't removed from my inventory. I can still talk to the "older" Modwyr.

I wasn't able to replicate the bug: I went through the conversation couple times choosing the same and different paths as before but Modwyr gets removed properly. Here are save game:

Before:

https://drive.google.com/file/d/1JVQ3Lgr7yhzOkpCT8mk087_QPhV0BGF-/view?usp=sharing

 

And after with two Modwyrs:

https://drive.google.com/file/d/19DOHFKoSvHIZIGjWxr11UNphJ5Qk3Cr2/view?usp=sharing

Salutations Wormerine, 

 

Thank you for reporting this issue, it is one we've had previously but didn't have save files of the issue occurring so this helps us greatly. This should help to see if we can fix the issue, but until then enjoy the additional conversations with our favorite blood thirsty steel implement. 

 

- Chelsea