Yes, the hub is identical
Same 5x120 PCD and same 67.1 mm centre bore: wheels from MG Marvel R bolt on and centre on Opel Insignia OPC without rings. You still need to check the offset and tyres, detailed below.
≈: width estimated from the original tyre size.
Wheel by wheel: offset and tyres
Each original wheel from MG Marvel R is compared with the one from Opel Insignia OPC of the same diameter: how much closer the wheel gets to the shock absorber or how far it sticks out of the wheel arch, and whether the tyre keeps the same overall diameter.
- ✓
≈7Jx18 ET50 · 215/55R18 — Fits like the original
Compared with the original 8Jx18 ET41 on Opel Insignia OPC: shock absorber side −3.7 mm, wheel arch side −21.7 mm, tyre diameter +3.7 % : fit it with the original tyre size of Opel Insignia OPC (235/45R18), not that of MG Marvel R.
Comparison for guidance only (estimated width). Check in detail
Before fitting the wheels
An identical hub is not enough: offset, width and diameter change the position of the wheel, and larger calipers can touch a smaller wheel. Original wheels often use bolts or nuts with a specific seat: keep the fixings intended for the wheel, with the thread of Opel Insignia OPC (Ecrous - 14x1.50), tightened to the torque shown on its vehicle page. Finally, check that the size is among the approved fitments for your vehicle. This comparison is for guidance only: have the fitting approved by a professional.
And the other way round: wheels from Opel Insignia OPC on MG Marvel R?