Should be at least as good as the S10 in call quality. The only Samsung flagship that ever had call quality issues that I can recall in recent memory was the S9 Plus. There were a few batches that did not handle carrier-based HD+ Voice very well. I owned an S7 Edge, Note7, Note8, S9, S10, S10 Plus and all were fantastic with call quality. I do recall the S9 Plus issue though, and even knew someone whose phone had that issue.
Long story short, there's a very good chance that call quality is immaculate, but mustang7757 is right.