Migrated from Bitwarden to 1PW: having problems getting 1PW to recognize apps

Hello FrankBreech thanks for your question. If a Login was created outside an app, such as through an Autofill prompt in your browser or directly in 1Password, you will need to link the item to the app. After the first time you approve 1Password to use a specific Login for a specific app and sign in successfully a link between the two will be created.

Those links won't be imported from other password managers but website links can be. If the URL is saved in the website field of a Login item 1Password should offer the Login on that website. Do you have Login items for websites with the appropriate URL saved in the website field of the item that are not previewed?

As to your last point, Autofill on Android doesn't have the same associated domains stipulation as Apple's Password Autofill framework does so the behavior will be different.