Excellent advice above. He always gives spot on advice that guy.
When I quote for panelling I always give both options to the customer when I visit and sometimes even give them two prices; one for solid panels made in the joinery and one for faux panels made on site with a ply backer board, applied timber ‘rail and stiles’, applied ‘raised panel’, and ready made mouldings to face it all up and finish off. This latter option is faster and cheaper - especially for stair panels - and suits a paint finish as there are a lot of pinholes because it is often all shot together with a nailer. It is also easier if you have to cope with existing electrical outlets and switches etc. I probably do 5 of these faux panelling jobs for every traditionally made one. In fact, I pretty much only make up panels in the workshop if they want an oak finish.
If you want to make solid panels and you don’t have a spindle moulder you probably could find the right heavy router bits by looking at the tooling designed for making (cupboard) doors. The Inspector’s advice is good on this as well. You could just make squared non-scribed rail and stile frames with a panel in a groove - you can actually raise a single bevel panel very much like the one in your picture with a hand plane or a table saw - and use the off the shelf mouldings to finish it off.
