An APK breakdown that involves XDA developers and 9to5 Google has revealed that Google's Phone App section might get an app which not only records telephonic conversations but also transcribes them. The 44th version of the app, which is the most recent one not only contains the code, but the way to legally implement it as well.
The transcription facility for the call also exists within the app, much like the Reorder transcription app Google has already launched. Google has put a warning which reads, "When using the call recording feature, you are responsible for complying with applicable laws related to the recording of calls. Please be aware that many jurisdictions require the consent of both parties for such recording." Later an auto generated voice declares to both speakers that the call recording has begun or ended. This is because, within some states of America, there is a policy which requires both parties to consent to a call.
The XDA Developers have also mentioned, "The Phone app will show a "record" button during any phone call once the feature is implemented. Tapping on that will start a recording, and presumably trigger the disclaimer to verbally inform both parties."
The APK is still under testing and the workings of the app hasn't been revealed yet. Hence, it is quite uncertain weather the app will be present in the next version of the phone app or not.