https://bugs.winehq.org/show_bug.cgi?id=44024
--- Comment #8 from Dox IngeniousDox@gmail.com --- This is a bug with Wine Staging since 2.18 where they implemented: Support for ECDSA certificate chains.
This was so Battle.net can be run in Win7 / Win10 mode etc. Before that you could only use it in WinXP mode. WinXP mode doesn't have the issue. But Blizzard is erquiring you to have Win7 or higher set to install games now.