If you are looking for the original 1999 experience or its modern counterparts, these are your best legal options:
: The original 1999 game requires specific patches to run on modern hardware, which are already included in the GOG and Steam versions. Homeworld (GOTY) Full Game Free Download
Websites promising "Homeworld Full Game Free Download" outside of official stores often bundle the game with: If you are looking for the original 1999