Is it this you are thinking of?
https://play.google.com/store/apps/details?id=com.catalinagroup.callrecorder&hl=sv&gl=US
Does it replace your regular dialer also?
What is the difference between the Play Store version of ACR (https://play.google.com/store/apps/details?id=com.nll.acr) and the ACR "unChained" version from APKMirror (https://www.apkmirror.com/apk/nll/call-recorder-acr/call-recorder-acr-33-6-huawei-unchained-release/call-recorder-acr-33-6-huawei-unchained-android-apk-download/)?
Does one have more functionalities than the other?
An "unchained" version is available via APKmirror:
https://www.apkmirror.com/apk/nll/call-recorder-acr/call-recorder-acr-31-1-unchained-release/
Manually installing this worked fine for me. I had the Google Play version with a pro licence and had put off receiving the update. Installing this version from APKmirror installed overtop of the existing program as an update (which makes me more comfortable that this is the exact same program) and Play no longer wants to update. The app remains as an installed app on Play, so I don't know if future updates will overwrite the "unchained" version.
No number issue: https://nllapps.com/no
Sd card issue: it is not possible to use Sd card with Acr and I have no plans due to complexity of this. You can however, try my new app ACRPhone from https://play.google.com/store/apps/details?id=com.nll.cb if you have Android 7,8 or 9
Android 9 plus does not support 2 way call recording with 3rd party apps. No call recording app can record properly. Some phones can record from the earpiece speaker fairly well. You can also try setting audio source to MIC, recording format to MP3 and Audio gain to 14 under Recording settings. It might improve the audio quality.
For that to happen phone app should have intents regarding that it registers. I am not aware of such intent. I don't expect to find any.
However, while acr does not have functionality to import files form other folders, our sound recorder app called ASR indeed has Folder Watching functionality that you cna use to import recordings from other folders.
Check https://play.google.com/store/apps/details?id=com.nll.asr