If they aren't any LocalScripts in my game will FilteringEnabled not be a problem?

This question isn't so easily answered.

First, it's important to say that regardless of if you have LocalScripts or Scripts in your game, if your game is programmed correctly, it should work with Filtering Enabled.

You shouldn't refuse to use LocalScripts because you're afraid of how they change with Filtering Enabled.

Filtering Enabled shouldn't be a problem if you program the game properly. You should have Filtering Enabled regardless of the game or your scripting level.

Filtering Enabled affects how the client interacts with the server more so than it changes how the server interacts with the client, so LocalScripts will behave more differently than Scripts. But that does not mean that you're game will be 100% save if you only used Scripts with Filtering Enabled.

If you're curious about something more specific, feel free to post another question.