About to pull the trigger on Pura 70 Pro/80 (or maybe P60 Pro) - a couple of questions

My LG is slowly dying and I've been looking for a new phone. I don't really need google that much, just email and maybe android auto. But anyway, can someone explaing the difference between EMUI and HarmonyOS versions?

1. I know that EMUI can run android apks natively after installling microG and that HarmonyOS (next) can't - it runs them in a container, But I heard some people saying EMUI is trash and slow and Harmony is better, but why?

From what i learned HarmonyOS versions 1-4 are still android and can run apks natively.

2. Like if I buy Pura 70 Pro/80 (global), will it arrive with emui or harmonyOS? Will I be able to upgrade to it later? So, all of the EMUI versions from 12 to 15 are based on android 12?

3. What about apps? If I have installed some apps (like banking ones, or Curve) on EMUI will they stop working after upgrading to HarmonyOS NEXT?

4. Is it worth making chinese huawei id if I'm from Europe? I heard chinese versions of HarmonyOS NEXT have more features but are they in chinese? Will chinese OS support other languages (eg. polish)?

5. Are there differences between global and chinese version of the phones? more or less bands? Will I be able to install global rom on chinese version? would it be worth it?

Thanks in advance.