Numerous times I have found myself up against players with extremely offensive names (that I dare not even type in here).
These names are not family friendly, they clearly go against TOS for Blizzard games in general, and we have 0 way to report them.
Where you see the other player’s name in the top left (on computer version at least) you should be able to right click (or tap in phone version) to bring up a list of options:
-Send friend Request
-Report player name
-(etc if other options might make sense?)