acquiring masamune

I read that the Masamune is located at mushroom rock, and that I gotta insert my rusty sword into a statue of lord mi'ihen or something, but I cant see any statue at Mushroom Rock. Help me please!

Thanks to any and all that help

I am wondering, would this statue be the one right outside of Luca?

Doesnt seem like that one has any option to insert the rusty sword so I still dunno where this statue is.

There should be a green square on the map, you arent allowed to go that there when you first go to Mushroom Rock, but you can now. The green square is a platform that rises to the statue, and you explained the rest.

to get there u have to go down the right most path when u enter mushroom rock, then take the next left. i.e. the 2nd left from when u enter the screen.

however, if u enter this way you will encounter the dark magus sisters so to avoid them, approach mushroom rock from the djose highroad. in this case it is the 1sy left that appears on the screen.