The simple answer to your question is there is no difference between the injectors and fuel pumps for a 2 stroke or 4 stroke engine.
There are numerous variations on the basic design of the cam driven Bosh plunger & barrel type fuel pump fitted to most engines with respect to how it is controlled to regulate the amount of fuel injected per stroke, and how it may be mounted on the engine as either independent pumps for each cylinder or number of pumps, 1 per cylinder, mounted in a block assembly or combination pump & injector assemblies activated with a rocker arm. The exception being many of the more modern engines fitted with electronically controlled injection systems, these engines have what is known as a "Common Rail" fuel system and a high pressure booster pump is used to supply fuel to the injectors which can be driven directly by the engine, by an electric motor or a combination of both.
Injectors are designed to be opened mechanically, electronically or by fuel pressure pushing against a spring. All do the same job, supply a fine spray of atomized fuel through a nozzle to the cylinder, so it makes no difference if the engine is a 2 stroke or 4 stroke.
Troubleshooting 101 "Don't over think it - K.I.S.S. it"