The distributor one is suited for CNG but this generation of 7AFE came with oil burning issue. You can search online about 7AFE Oil burning and you will find a lot of people talking about this. Toyota fixed this issue in the next generation 7AFE that is the coils ones and that coil one also comes with lean burn function.
I also got 7AFE in my car you may take a loot at this thread.
https://www.pakwheels.com/forums/d-i-y-projects/182351-7afe-swapped-into-corolla-1998-a
BTW Which car r u going to swap this engine into? now a days thx to generator makers its very hard to find 7AFE and they are also expensive now.