Oyster sauce is relatively less salty as compared to soy sauce. Sometimes other sauces like hoisin sauce, soy sauce, or even vinegar are added to oyster sauce to enhance its flavor. It can be further thickened by the addition of other sauces. Having a dark brown color, it has a texture and consistency similar to caramel. When compared with oyster sauce, soy sauce is thin as well as salty, so a good substitute. You can add a teaspoon of sugar, brown sugar or other sweetening agent to make it less salty. So, depending on your preference, various types of sauces such as hoisin sauce, fish sauce, sweet soy sauce, teriyaki sauce, mushroom broth or sauce, or Worcestershire sauce, can be used as a substitute for the oyster sauce in your stir-fry. Nor does fish sauce have the rich, caramel qualities. Fish sauce has a watery appearance with an acrid aroma. This aroma goes away when it is poured into a recipe.
Conclusion
While there are many sauces that can be easily made or are available in the market, it is difficult to replace oyster sauce with its unique flavor, making it one of the best sauces there is.
