Angel fish chasing my strawberry Tetra, what should I do?

Do you have a tall slimmer tank or a normal rectangle shape tank? If it's tall and slim, the angel probably won't bother the algea eater b/c angels tend to hang out towards the middle/top and won't go to the bottom of the thank to bother fish..usually, but exceptions to everything. They might bother the sword, but I don't know. Angels love love love plants and they love lots of them, line the back of your tank with plants, see if that distracts them and makes them happier. They are a semi agressive fish and the tetras are a community fish, you take a risk mixing them, I'm sorry, but that's just how those fish are. Try the plants and see what happens or get a take divider and just divide the angels from the rest of the fish.