Graphite I was able to successfully test ACR Phone app from Aurora Store, and using the Helper app (found on their website).
The Helper app does need Accessibility, which is possible to enable.
@Graphite did you try recording a call? When I tried, after granting Accessibility to APH and enabling call recording in ACR, that the call recording function does not get access to caller audio but only phone's mic and therefore appears to require speakerphone to be on (I'm guessing to record caller audio through phone's mic). My recording was only of me talking, not the other party, unless I put the call on the speakerphone - then both side of the conversation get recorded.
Is it the same for you or am I missing something?