does this feature exists in any waves-viewer in xschem to see value of exact point as the figure shows ?

in Xschem pressing the '`a`' key when the mouse is inside a graph brings up a vertical cursor. You can move or reposition the cursor with the mouse. All waves show the value at cursor position. Right button clicking when the mouse is close to the cursor allows you to set numerically the exact cursor position. There is currently no horizontal cursor intersection detection.