You’re cooking them to death. Lower heat, add some water, cover with a lid to steam them. If you want a slightly blackened outside, do the above then take them out, raise the heat, and braze them quickly so they don’t dry out.

You can rinse them in warm water first and let them drain for a while. Or you can add more sauce to your stir fry as you cook, ie soy sauce, or whatever you are using.

Use a good olive oil and don’t worry about cooking the water out.

What I usually do is set the burner on medium and cover the pan. Also, I use a large enough pan that the vegetables can spread out a bit.

Depends on the dish. If it’s a separate side dish, I generally put it in a pot with a small amount of water and boil them for a few minutes, drain and then toss in a bowl and season.

If it’s in a dish with sauce, (think something along the lines of a brown gravy, or a curry, etc) I’ll throw them directly in near the end as to not overcook.

One thing I’ve started doing that helps is throw them in the air fryer for a couple minutes and get the water drained out. Then put them in the stir fry.

No one has yet mentioned soup, so I will. Particularly for freezer burnt veg, whacking it in a blender with some stock and herbs can be good.

Risotto/stews/curries/pasta bakes can be other options, depending on the veg. If they’re in a sauce, then ‘cooking the water out’ becomes less important.

I microwave them and add them to something tasty like a sauce or curry to conceal them.

Boil them. 1/2 cup water per 1 cup veggies.

Steaming works, too. Add less water, cover, simmer well.

Season them, too. Salt, garlic powder, onion powder and some MSG go a long way with bland frozen veggies.

Add olive oil?

I usually only steam frozen veggies. Then after steaming I might stir fry. If I do the second I pull them a little before they are soft on the inside.