I‘ve been using Spamsieve for a while, and it works rather better than the in-built mail filtering in macOS.
There’s not much you can do about most any tsunami of spam, beyond the ever-unpopular changing of your email address, or through filtering.
In this case, bulk filtering by language at the mail client or (better, if the server filtering tools are accessible to you) filtering at the mail server is certainly possible.
If your mail provider implements and allows access to SpamAssassin or other tools at the mail server, that can work quite well.
My experience with the integrated spam filter in macOS has been poor.