Any EASA licensed engineer or mechanic should be able to sign your logbook entries, providing what they have signed is within the scope of their licence and they saw you/assisted you with the job, eg B2 sign for certain avionics bits, A licence holder can sign for wheel changes etc.
Make sure you keep a signature sheet at the front of your logbook where you can note the licence no.s of the people that have signed your book and get the shift supervisor/line manager/QA to authorise them.
That's the way I did it and didn't have a problem.