I don't know if there is a market stripper for emulsion, but if it is
really thick, it is possible to use a steam stripper (I have done this
and it works) it won't remove it all but anything likely to peel will
loosen off.

The only way to soften the edges of the bits you have scraped off is
either filler or a scim coat of something fine like plasterboard
jointing compound.

In many cases I have unibonded and re-plastered the ceilings at the
customers request.