Pokémon Altair and Sirius English translation
ポケモン アルタイル/シリウス · Pokemon Altair · Pokemon Sirius
Dr. Akimbo's English patch for the notoriously hard Japanese Emerald hacks that started the Vega series.
The hacks
Altair and Sirius are two versions of the same fan game built on Pokémon Emerald. Part of the roster is replaced with original creatures, there are new attacks and changed evolution paths, and a handful of new maps and tracks. The real draw is the challenge: gym leaders are smarter and stronger than the trainers around them, and you will usually be under-levelled when you face them.
What's translated
Dr. Akimbo, who also translated the sequel Vega, put the Japanese text into English. The English patches for both versions were last updated in June 2019.
Playing it
Pick one of the two versions and apply it to your own copy of the game following the translator's instructions in the release thread.
The screenshot shows Pokémon Emerald, the game these hacks are built on.