Which is more natural expressions?
1. We will start addressing this issue as soon as possible.
2. We will address this issue as soon as possible.

Question

Which is more natural expressions?
1. We will start addressing this issue as soon as possible. 
2. We will address this issue as soon as possible.

Answer

My vote is #2 (We will address this issue as soon as possible). #1 doesn’t sound bad, I just feel like using “start” isn’t necessary because it is implied. 🌈

Nicky 🤗

Answer

Both sound fine.  #2 is better because it is more concise.
Your question could be written better as, "Which of the following sounds more natural?"  or  "Which sounds more natural?"  or  "Which expression is more natural-sounding?"  or  "Which is more natural?"