How to extract the stress value in the beam?

Say there is a simple supported beam with load at the end point, how to extract the shear stress at any ts in the beam? When I simulate this case, the shear force at any ts in the beam is the same!

Hi, you can use the BeamForces component to find these values: 3.7.10: Beam Forces - Karamba3D 2.2.0

so the stress should be Vy/Area?

That would be the average stress over the cross section, but if you are interested in a specific point in your cross section, you would need to do further calculation. You can refer to Beam Stress & Deflection | MechaniCalc