power of autarky when your no longer here

I'm not sure what you are asking. If you have already appointed all three as Poa, then the deed is done. Did you ask them beforehand if they were happy to do it? Have you changed your mind and want only one poa?

autarky is apparently a dog food

If you've appointed them, then they are.

I have appointed them and would like your opinion

I have 3 daughters who is my power of attorney

None of your daughters will be Power of Attorney unless you have legally appointed them. Have a chat to them about it. Plenty of info on Gov website.