In most cases, combing through the coat will remove dirt or dust, without the need to bathe the cat. If the cat has one place that's smelly or dirty, then try wiping the area with a clean, damp facecloth or an unscented baby wipe.
Take it very slowly! Anoint different items with each other's scent and place them in different rooms while the cats are visually and audibly blocked from one another. Feed them...
Put tea bags in each boot, multiple if necessary! If that doesn't work, mix baking soda and essential oils together, put them in little bags, and leave the bags in...
Be aware that cats do feel stressed when overcrowded. Be realistic about how much space there is in the home, and don't add another cat if it means living on...
This depends a lot on the cat's personality. Some previously outdoor cats actually prefer to be indoor cats as they feel more secure. The trick is to provide ample opportunity...
A truly feral cat is unlikely to adapt well to an indoor life. A feral cat is uncomfortable with human company and may well feel trapped and be very unhappy....