C-414 pilot reported engine failure during departure climb. Diverted and returned to departure airport and landed uneventfully.

Narrative

Departed ZZZ at XA:19 headed on an IFR flight to ZZZ1. On departure turned to 320 and was eventually clear direct to ZZZ2. As we were climbing through 12000 ft the fuel flow on the right engine started to decline. I had been monitoring all cylinder temps and EGT's through the climb and did not notice any abnormality. I ensured mixture was set full rich and then checked the electric fuel pumps were both on; they were on low. I move the right engine to high boost and turned on the vent heat just to be sure I did not have any ice; not likely; it was dry and clear air. I had to lean the engine when on high boost; to keep it from flooding; but after just a moment fuel flow lowered again. I decided then I was losing the engine and [requested priority handling]. This was only moments after being cleared direct to ZZZ3. At this time; I made the decision to shut down and feather the right engine. I moved mixture to ICO (Idle Cut Off) and moved prop to feather. Closed the throttle; shutoff MAGS on right side all while moving to full power on left engine.Ensured auto-pilot was off and yaw damper was turned off. Raised dead engine and used both rudder pressure and rudder trim to minimize skid. At this point I had been clear direct to ZZZ which was only about 13 miles off the nose. I maintained a reasonable descent profile maintaining airspeed well above blue line and conserved altitude until over the aerodrome for ZZZ. I entered pattern from a right base at almost 4000 AGL. Once I overflew the airfield; I circled to land on Runway XXR by making a gentle left 360. Once over the airfield; I arrested the descent lowered first notch of flaps and then the gear. I continued on the same descent profile until lined up on runway. I was a bit high but able to correct and made landing on XXR without incident or damage to solo pilot and single passenger or the airframe. Made Taxiway 1 turnoff. Was unable to taxi to hanger under single engine power so shutdown on taxiway and was towed back to hanger. The engine had lost most of oil from through the oil filter bracket. The oil had been changed just prior to this flight and was found to not be sufficiently torqued. The safety wire was in place; however; we were able to torque another 1/2 to 3/4 a turn. The root cause was determined to be loss of oil pressure due to near oil starvation because of faulty oil filter installation. No injuries or air frame damage.