You can't through normal means. If you're on Catalina (10.5.x) or higher, Diablo 2 won't work.
Workarounds would be:
- Installing a virtual machine (i.e. virtualbox) and Windows on it.
- Obtaining the CrossOver Mac software to run windows and through that Wine / Diablo 2
From last i heard (over a year ago), the Wine method no longer works either since most of its dependencies are 32-bit, but maybe they updated it to work with 64-bit? Who knows.