Newsflash: What would you do?

We bought a new build and were the first on this street and the adjoining street. December would be our 2yr anniversary in which we could sell without paying tax on gains. We sold our 1yr old brick ranch in TX and moved to SC, but still had to pay a portion of tax gains (relocated due to work).We’re having issues with our neighbors and no one is helping (HOA or sheriffs). Their backyard adjoins to the side of our backyard on the left. In the past, they’ve trespassed and even after they installed a fence, were caught trespassing and trying to plant arborvitae shrubs in our yard. They built a fancy kiddie pool, and due to the slope of their yard, we can always see them (they’re out there every frickin minute of the day & night) and obviously hear them. I should note that we can hear anyone outside from any point inside of our home. We’re used to brick homes, so I’m not sure if that is normal for a vinyl-sided home? We’ve filed a noise complaint for the late night loud gatherings and also looped the HOA in. HOA also knows about their illegal dog breed who was waking us up barking every morning. That has drastically reduced. They also drain their pool near the fence and it naturally drains into and across a portion of our yard. HOA was told about this issue too. There is an easement (Storm Water drain clean out access – behind our property) on a portion of both of our backyards and local laws say we can’t plant anything there. How could we if their pool water is coming into our yard and killing off vegetation? The neighbors planted a few scarce arborvitae along the fence, but they’re small and there aren’t enough of them (or room for more). When it rains, the water runs through our yard in the same spot, so I’ve considered French drains, but not sure with the easement being there. Workers could easily access the clean out by going through the water retention “pond” behind our home. Said pond does not actually hold water.The wife is a sheriff (supposedly) and husband claims to have been on the HOA board of their last neighborhood. We obviously do not have a good relationship with these people and feel like we can’t enjoy OUR backyard. They’ve blatantly lied and tried to gaslight us that their fence is not on their property line and that’s why they’re in our yard. We showed them the plat maps and even called out a county surveyor to prove their lie. They also lied, saying that they aren’t draining their pool. I have eyes and can see the hoses and large amounts of water coming into my yard..We also have a few neighbors that ride their atv and dirtbikes on our street and the retention “pond”; It’s insanely loud inside of our home. Sheriff said they can’t enforce since these are private roads here in the neighborhood, and that we should complain to the HOA. HOA says to call the sheriff… We’ve never lived in a vinyl home before, so I’m not sure what can be done about noise reduction. How much would landscaping really help? Should we look into replacing windows and swap the vinyl out for Hardie Board, or should we cut our losses and move?