Can a B-rated EASA Part-145 ‘Engine shop’ remove Engines (in serviceable condition) from Aircraft and certify them with an EASA Form-1?

If it is from an aircraft that is still in service, you need to have an A-rating (aircraft maintenance) , so NO.

If the aircraft is withdrawn from service and being dismantled, it is also NOT possible that a B-rated ‘Engine Shop’ issues an EASA From 1 for removal of serviceable engines, as AMC2 145.A.50(d) details the following:

(a) Aircraft withdrawn from service are sometimes dismantled for spares. This is considered to be a maintenance activity and should be accomplished under the control of an organisation approved under Part-145, employing procedures approved by the competent authority.

(b) To be eligible for installation, components removed from such aircraft may be issued with an EASA Form 1 by an appropriately rated organisation following a satisfactory assessment.

In this case, appropriatelly rated organisation means an A-rated (aircraft maintenance) organisation.

The only option for a B-rated ‘Engine shop’ to issue a Form-1 for an engine is to receive the engine in the Engine Shop and perform a Inspection/Test.