Click on the link below to download the PDF document which tells you the changes on all 251 Pokémon movesets in this game from their original moveset in Gold.
https://www.mediafire.com/file/rfrc2lwxc7jo9hu/Gold-Sinnoh-Movesets-changes.pdf/file
Or, you can view these images, which are the pages from this PDF document :
Pokémon Gold Sinnoh 