I would avoid fresh garlic no matter what method you use to can. Granulated garlic works and the risk is basically nil. If you have homegrown garlic that you want to use, I'd dry it (oven or dehydrator) and then pulverize it in a coffee grinder/food processor/mortar and pestle, and only then use it an canning recipe.
Some things can't be canned due separation issues, even with pressure canning. Like pumpkin and homemade mayo. However, things like salsa, that you can pressure OR hot h20, the recipe should stay the same except the time it takes to pressure can it should be much less than the hot h20 bath. Stuff like green beans, homemade soup, meat, and marinated veggies must be pressure canned.
HTH