Well the title is self explanatory; any game with a good pregnancy or at least X-ray Cg or animation, could be anything from RPG to RENPY to HTML and so
https://f95zone.to/threads/my-legacy-saddoggames.1356/
You play as a man with schizophrenia, whose split personalities compels him to impregnate his visiting 2 nieces and sister in law. Can get pregnant harem ending.
https://f95zone.to/threads/the-tyrant-v0-75-part-2-saddoggames.6025/
Made by the same developer as the one above. Pregnancy is not yet implemented, but is mentioned all the time, and no doubt going to be impemented before long. You currently have the option to make your mother agree to allow you to knock her up, and both your sisters know that you plan on knocking them up as well, so I don't think it will be long before it happens.