Plaster roses can be fixed to the joists above (through the plaster ceiling) with screws. It's also possible to fix them with plaster adhesive, but they might fall down.
There is probably a round section moulded into the middle that you can cut out for the electrical fitting. Electrical roses are about 100mm so will conceal a hole up to that size.
Add one or two screw-in vine eyes, screwed into the joists, so you can hang your chandelier or other lamp off them.
The screw heads can be concealed with filler, before painting them, and the eyes, to match the ceiling.
BTW my neighbour has a listed building, the council's conservation officer has a list and photographs of the original features, including an ornate ceiling rose that he didn't know is actually made of polystyrene painted white.
To amuse themselves, the builders unfastened it and dropped it on the floor during one of his visits.