JAR-FCL1 allows for the PPL Skill Test to be taken on either a single-engine or a multi-engine aeroplane, although there is no provision for asymmetric exercises in the Skill Test Schedule.
There is a requirement for 70hrs experience as pilot-in-command prior to the issue of a MEP Class Rating, which also applies to a PPL gained on a MEP aeroplane. It would, therefore, be necessary to complete a minimum of 95 hours training (25 dual and 70 solo) prior to issue of the PPL with MEP rating. Furthermore, a Registered Facility cannot provide training for the MEP Class Rating and so a PPL on a multi-engine aeroplane could only be completed at an approved FTO.
Is it possible to do a PPL on a multi-engine aeroplane? - Yes; Is it practical? - No.