To Align Objects Between Viewports Using a Construction Line

Click Drafting tab > Draw panel > Xline drop-down > Construction Line.
Specify a point in the first viewport. Specify a second point to determine a line for the alignment.
Choose a point that can be aligned with objects in the second viewport. Use object snaps for precision.
Click Drafting tab > Modify panel > Move.
Select the viewport to align to the first viewport. Press Enter.
When prompted for a base point, specify a point in the second viewport. Choose a point that corresponds with the point selected in the first viewport.
When prompted for the second point, hold down Shift and right-click. Click Object SnapPerpendicular.
Click the construction line you created.
The first and second viewports, and the objects in the viewports, are aligned.

Note: When aligning objects in viewports, the scale of the viewports should be the same.