If you're already a HSBC Premier holder, you can open foreign account but need to first validate via any HSBC Branch or your Relationship Manager then they'll route it to International Banking Centre (IBC) to take over after thumbprint verification.

There's no premier fees in other country - since the qualification comes from Malaysia (>250K holdings, Perks@Works, or >1mil mortgage loan with HSBC). But there might be minimum holdings required depending on country you're opening the account. Note that you can only open Premier account overseas, not basic ones, via the Premier International banking feature.

Tho for Singapore I'd rather to go with CIMB route since it's practically free and you don't have to worry about premier status or minimum holdings; or Maybank which only requires $1K SGD holding

All Singapore banks allow you to withdraw foreign cash. You need to pay
1) 1-2% in withdrawal fees
2) markup exchange rate

Your choice I wouldn't bother with withdrawing foreign cash in Singapore especially when they have lots of good overseas travel card from revolut, instarem, transferwise and revolut.

It's possible but there is a handling fee of 1.5%. This fee applies to cash deposit as well as cash withdrawal in any currency other than Singapore Dollar.

There are however, ways of getting around it. Like when you withdraw from HSBC UK ATM in either Pound Sterling or Euro from your Everyday Global Account. And cash withdrawal at HSBC Group ATM worldwide is free of charge for all HSBC Premier/Jade/Private Banking clients.

Another way is to withdraw the foreign currency at HSBC Hong Kong. For this you must also be a HSBC Hong Kong client.