Using ExtrudeShape it is straightforward to obtain a bevel along the edges parallel to the extrusion direction.
https://www.babylonjs-playground.com/#VKIXD8
As far as I know there is no function to produce bevels along all the edge but you can extrude and lathe a set of shapes to form such a mesh, for example
circular bevels - https://www.babylonjs-playground.com/#VKIXD8#5
straight bevels - https://www.babylonjs-playground.com/#VKIXD8#6
different size bevels - https://www.babylonjs-playground.com/#VKIXD8#7, https://www.babylonjs-playground.com/#VKIXD8#8
EDIT Previous errors in PGs are corrected