I have never been able to find any comfortable earplugs despite trying several makes and designs. I even had some custom-made silicone earplugs made but they are frankly no better. After about one hour, they are too painful & I have to remove them. Even after a short break, things don't really improve much. The discomfort is distracting, obviously not good for safe riding. The only thing I can use for extended periods is cotton wool which reduces some wind noise but not much. According to the custom-made earplug people I have very small ear canals.
Some time ago I bought some differently designed earplugs but due to lockdown & Winter, I just put them in a drawer & forgot about them. I rode the bike on Thursday for a couple of hours & thought I would try them out.
So far so good! The noise blocking was effective and more importantly they were very comfortable to wear. They sit flat in the ear rather than inserted in the ear canal which is why they are probably more comfortable.
https://www.happyears.co/uk/
In the photograph, the model has the stem of the plug horizontally but I found having it vertical pointing down to the bottom of the ear was more effective at reducing noise but still comfortable.
Their customer service is excellent, they have answered my emails over the weekend promptly.
So if you have had a problem finding comfortable earplugs, these could be the answer!