A budget-friendly alternative to a traditional porch screen is outdoor curtains. Depending on how much privacy/shade you want, you could choose from opaque curtains or sheer net curtains.
Bamboo shades are a good option because they’re inexpensive and lightweight. However, they’re not as weather-resistant as treated fabric curtains, so make sure you take them down during wetter weather.
If you want actual porch screens, the best material to use is fiberglass mesh. It’s less expensive than metal mesh and is safer around kids and pets because there’s no risk of injury.
It has good weather resistance, but the specifics depend on the thickness you use. Also, bear in mind it could make your porch very warm, which could be nice in the winter but less so in the summer.
Artificial hedge will give you plenty of privacy but won’t be as weatherproof as traditional porch screens. Also, it’ll still let bugs through, so bear that in mind if either of these factors are a priority.