After a quick search for "Fresno" here in the Knife Laws forum it appears the consensus is that Fresno follows state laws with no knife laws of it's own.
On this site you can search through all of Fresno's laws (type "knife", "blade", etc into the search box). It's a reliable source-
https://library.municode.com/ca/fresno/codes/code_of_ordinances
I did a few searches there and couldn't find any knife laws (at least not any that apply to carrying a knife). That indicates that Fresno follows California state law when it comes to knives.
So I'm convinced that it's perfectly legal to openly carry any size or type of fixed-blade in Fresno, just as it's legal to do so under state law. With the usual exceptions- no school property K-12, no secure areas on airport property, and no government building. Also, no fixed-blades with blades longer than 2.5" on university property unless it's for work or food prep in or around your residence (Ca penal code 626.10).
There are a few counties and cities in California (like Los Angeles) that do have their own more restrictive knife laws, but Fresno isn't one of them.