Aunts. People normally refer to their "auntie" as just aunt (at least where I'm from) , so that might help you remeber the plural form. Aunt with an "s"
It is aunties.
I've seen it spelled either "Aunty" or "Auntie". I think the second one is probably more correct, since it didn't get underlined by the spell check program and the first one did.
Latches.
slides
Clouds
daddies.
axes
circus's
That is the correct spelling "princesses" for more than one princess.
Trophies
spell it out - there is more than one ADEA
I think perhaps you are trying to spell countries, as in more than one country.
One activist. Several activists.