ACR Pro 33.1 unchained - records but playback speed is wrong (too fast)
Boldbeast v13.1 - working OK, but only for 30s in free version, unless you start recording manually by pressing the Record button.
Cube ACR v2.2.176 - working OK, no need to buy premium (I recommend this app). Download .apk directly from https://cubeacr.app/
My phone is Samsung Galaxy S20+ 4G, Australian market, bought directly from Samsung, everything stock, no root.
Model SM-G985F, Build G985FXXU1ATBK.
To make Cube ACR work, I did the following:
Go to Cube ACR Settings -> Recording settings -> Phone recording audio source -> choose "voice recognition (software)".
Scroll down and turn on "Normalize Speed" setting.
Go back, Settings -> Miscellaneous -> scroll down all the way -> press each one of the four buttons and turn on accessibility settings, turn off battery optimization, and so on...
That's it, you should be all good. Try it and see if it records and plays back properly.
All "international exynos versions have call recording built-in into the software. To enable it, the right flag should be enabled in the cscfeature.xml file (you need root for that, unencrypt the file, modify it and overwrite it back again).
However I'm not sure if you can write to that product partition anymore, on the S20s (we cannot write to system directly anymore). Worst case scenario, a Magisk module could do it.
I'll try it now on my S20+ 5G (intl) and report back ??