I am experimenting using Ulysses as my editor for blogging now. Ulysses is great for writing long-form. I purchased Ulysses through SetApp subscription. SetApp is a nice subscription system for macOS apps from MacPaw. You might know them from CleanMyMac app, also included in the subscription for obvious reason.
Ulysses has integration features with popular blogging platforms, including WordPress. All you need to log in using your WordPress account and you can start writing. If you are using your WordPress using 2FA (Two-Factor Authentication), you will need to generate application specific password so Ulysses can interact with WordPress API.
WordPress itself also provides a desktop application, but I prefer to use tools I am familiar with first before trying new methods. We’ll see how this experiment goes in the next few weeks. I have so many ideas I want to write, but always hit the great wall of laziness.