I am just worried, that when I want to withdraw 2000$, then it is said, "Sorry, we need KCY".
Would appreciate if someone has experience with this. Thank you.
I didn't use Polo for many years, so I cannot really tell from experience, but $2k is a rather small amount and they should not cause troubles, especially as their help page tells:
Level 1 accounts can withdraw up to $10,000 USD per day by default. If you have a Level 1 account and enable 2FA, your withdrawal limits will automatically increase to $50,000 per day.
So
in theory you should be OK until $50k per day. However, also in theory they may ask for KYC even after the first 1$.
Keep in mind that since they're registered in Panama, they can easily work with different amounts than the exchanges obeying EU/US laws.