I'm working with a dyslexic adult who is trying very hard to pass the numeracy test for PGCE training. (She won't be teaching maths)
She is more motivated and has more awareness of how she learns, and of the fact that she needs to do regular practice and work at it to remember things, whereas children often don't want that.
Her knowledge is quite patchy compared to children, where it is slightly more obvious what level overall they are at - she will remember some random bits from school, though not necessarily how it all fits together.
She doesn't have the time that children have to spend ages practising times tables for speed, for example, or all the mental calculation practice that they used to do in primary school, which would help.
There much less need to try to make the lessons fun and full of games, the way I need to with reluctant children. On the other hand, sometimes games or silly mnemonics or whatever are quite good ways of learning things, so there are times when I will use some more childish explanation, and tell her 'this is how I first introduce this to children', so that she can still have the explanation, but not in a patronising way. I have to work hard to make sure the relationship doesn't become too one-sided/always me being the authority.