That ingredient is fine, but I wouldn’t comment that all products with it are safe given I don’t know other ingredients in those products.

Very few things are technically studied in pregnancy because the correct studies to do are actually unethical to perform. Sodium hyaluronate is the same thing as hyaluronic acid except you’ve replaced a hydrogen with a sodium, they then can form long chains and group themselves together. They’re pretty much interchangeable and aren’t considered to be different. They’re already found in your skin as well as many other parts of your body, so should be fine in pregnancy. Info here: skincare ingredients to avoid during pregnancy