There is no official GBA version of these games. Any claim of a "GBA download" for Diamond/Pearl would be:
If you are specifically searching for because you prefer the GBA style (single screen, pixel-art graphics, simpler mechanics), you are in luck. The ROM hacking community has created incredible "demakes" that shrink Sinnoh into the GBA engine. Pokemon Diamond And Pearl Gba Download For Android
: These are comprehensive GBA ROM hacks that feature the Sinnoh region, Gen 4 starters, and even modern Gen 8 mechanics. Pokémon Diamante Deluxe 🎮 Pokemon Diamond & Pearl GBA Download For