The digital re-releases feature wireless trading capabilities between different 3DS users, in place of the old-fashioned link cable – just as the case was with the re-releases of Pokémon Blue, Red, and Yellow Version on the eShop. If you intend on purchasing either of these games form the eShop, be sure to download the version with the correct language for you, as the various versions in different languages have all been listed individually on the eShop and labelled for your convenience.
There is also a bonus for purchasing either Gold or Silver directly off of the 3DS eShop that can be utilized in Pokémon Sun, Pokémon Moon, Pokémon Ultra Sun, and Pokémon Ultra Moon. If you purchase either game between September 22, 2017 and September 21, 2018, you will receive a code that can redeemed in any of the above Pokémon games in order to receive the legendary Pokémon Celebi as a mystery gift. Unfortunately, seeing how Celebi was an even-only Pokémon in the original Gold and Silver, there is no way to legitimately acquire one in the original games, and the code is only applicable to the newer titles mentioned above.
You can watch a trailer for the eShop releases below:
