I use Enpass 6.3.2 on OS X Catalina 10.15.2 and have been using Enpass for a while now.
If you are used to the performance of Alfred or 1Password on a 2017 Macbook Pro, the speed of the Enpass search is horrible. I have almost 1000 entries, which is really not much. Typing in a search phrase (it doesn't matter if I use the main window or the assistant), it feels very sluggy. The Enpass search is far away from being "responsive". It like Enpass a lot for its features and sync options, but have found myself searching again for an alternative as this performance situation is really annoying. I often have to wait seconds for the letters to appear in the search line! I hope this will be significantly improved in future versions.