Hi Booleano, for this kind of construction you can use the Boolean Intersection command.

There is a description here:
https://moi3d.com/4.0/docs/moi_command_reference7.htm#booleanintersection

Start by selecting the profile curves on one side:



Then run the Construct > Boolean > Isect command:



The prompt in the upper right corner of the window will say "Select second object set". At this point select the other profile and right-click or push "Done":




That will generate this result:



The way it is created will be the same as using the Extrude command on each profiles to make 2 solids that cross each other like this:



Then the boolean intersection command will slice up the objects and keep the part that is contained inside of both pieces.

You can do the extrusion first if you want, it's just a shortcut that you can give the boolean intersection command just the curves and it will do the extrusion automatically.

- MIchael