Pretty sure Erdős himself would be the first one to tell you that he was a minor footnote compared to someone like Euler (or Gauss, or Newton, etc). But it’s sort of a silly comparison, like asking who was the greater composer, John Lennon or Mozart? Vastly different times and milieus make the question somewhat pointless.

A (US) math friend once described it to me as Euler and Gauss creating the interstate system, and people like Erdös spending their careers putting up signposts on as many exits as they could spot. Some of those exits might turn out to be major highways of their own, but we can't tell until other generations of mathematicians take those exits and see where they lead.

Euler had way more impact than Erdos. Euler laid the foundation for a vast amount of applications. Erdos did establish probabilistic methods in graph theory and combinatorics but outside of that I’m not aware of other foundational breakthroughs of Erdos.

It is not even close. Almost every branch of modern mathematics includes an important contribution from Euler in its history. Erdos was a specialist by comparison.

If you sample a random person with a math degree, the probability that they believe Erdos had more impact than Euler is 0. ;)

Hard to compare as others have said, since they were from different eras. Personally I think Euler has made more of a mark due to his contributions to multiple independent fields spanning the whole of mathematics at the time.