Can I still pickle these eggs?

[GoodGuinea]

I hardboiled a dozen eggs (store-bought) 8 days ago, but didn't end up using them like I thought. They've been in their shells until today. Can I still pickle them, or are they too old?

They smell fine, but a few have yellow/green areas on the whites. I've never seen it before. It's not the yolk showing through. Still safe?

 

[Sussex19]

Personally I wouldn't, but maybe that's just me.