Okay I must say this first, Claudia is not looping like we see in movies like Groundhog Day or The Edge Of Tomorrow. She is not an exception. Her memory is not cumulative. She ages like all other other characters in the series. Claudia lives her life once just like everyone else. While Dark is a causal loop, this is not an infinite loop where the looper lives at the same age till the loop is broken. I wanted to put this theory to rest as many sites are talking about this.
That said. Lets get to your question:
There are two worlds, so there are two Claudias. No confusion there, as you mentioned.
Also, Eve's World's Claudia died well before she could have learnt about Quantum Entanglement, so Eve' World has only one Claudia.
Eve's World's Claudia dies at the hands of Adam's World's Claudia. Therefore Eve's Claudia never grows old beyond her 40s.
We're now left to believe that there was only one Claudia left operating. But there wasn't. There were two. Claudia-1 goes back in time to the point of the apocalypse and uses the moment when time stops to change the path of her younger self and result in Claudia-2. This is referred to as Quantum Entanglement in the series. Like you mentioned, Jonas are three as a result of Quantum Entanglement. Remember, a finite number, three.
Similarly, we have Claudia-1 and Claudia-2. A finite number of them, two. Each Claudia lives one path of her life. They possibly took turns doing the time-traveling and scouting for information and learning about the nature of the two worlds over 33 years. They would have had to regularly meet in secret to exchange information and notes to keep up-to-date.
But no one knew there were two Claudia's in Adam's world.
In the end, Claudia-1 accepts her fate and dies at the hands of Noah. But Claudia-2 stays hidden. She waits. Finally when Adam kills Martha, she reveals herself and explains that she used quantum entanglement to be there at that point.
I've spent 33 years looking for answers in your world and in hers.
I've tried to put together the pieces of the puzzle.
She has been doing this for a finite period of time, 33 years.
During the apocalypse, it stood still for a fraction of a second. And
that threw everything out of balance. But when time stands still, the
chain of cause and effect is also momentarily broken. One can change
things. Eva knows that. She uses the loophole in your world to send
her younger self off in one direction or another, in order to preserve
the cycle. And I used it to send myself in another direction, too. To
be here today.
This dialogue here adds to what I'm talking about. There were two Claudias in Adam's World thanks to Quantum Entanglement.