Does washing all types of meat (lamb, chicken, fish) make them ritually impure (najis)?

Washing permissible meats is permissible and does not lead to their impurity; rather, it leads to their purity if clotted blood adheres to them.

As for washing meats to remove what is thought to be residual blood in the veins, this is an innovation and contrary to the practice of the Companions, as they did not wash meat.

Shaykh al-Islam Ibn Taymiyyah clarified that eating roasted meat is permissible whether the meat is washed or not. In fact, washing meat is a Bid‘ah (innovation), for the Companions would take the meat, cook it, and eat it without washing. They would see streaks of blood in the pot, because Allah only prohibited shed blood, and did not prohibit what remains in the veins.