Quick answer to this question: No, the Samsung Galaxy A90, A70, A50, A30 models do not support rSAP.
Many Bluetooth handsfree kits in cars from Audi, VW, Porsche, BMW, Mercedes etc. only support the so-called "rSAP" profile.
The abbreviation stands for "Remote Sim Access Profile". With such a handsfree system with rSAP everything is controlled by the car and not by the smartphone itself.
In order to use the handsfree system, it is necessary that your smartphone supports rSAP.
Is rSAP supported by Samsung Galaxy A90, A70, A50, A30?
Samsung Galaxy A90 No rSAP is supported
Samsung Galaxy A80 No rSAP is supported
Samsung Galaxy A70 No rSAP is supported
Samsung Galaxy A60 No rSAP is supported
Samsung Galaxy A50 No rSAP is supported
Samsung Galaxy A40 No rSAP is supported
Samsung Galaxy A30 No rSAP is supported
Samsung Galaxy A20 No rSAP is supported
Samsung Galaxy A10 No rSAP is supported
You now know that the Bluetooth standard rSAP is not supported by the currently available Samsung Galaxy A90, A70, A50, A30 models. Models from other countries outside the D-A-CH region may have different technical specifications.