Earlier in MVC I used @Ajax.ActionLink
for Ajax call and replaced container in my layout.
Now in .Net Core there is anything like Aja
No. Honestly, you never needed it anyways. All it did was create a regular link and then add a trivial bit of JavaScript you can easily add yourself. Long and short, let it go:
Click Me
Then:
By binding to the class, you only need this one piece of JS for any link with a menu-item
class.