Some Questions About PS2 & Online Region Locking for PS4

Firstly I hope I have posted in the right place.

I am originally from the UK and currently work in Hong Kong and plan to buy a PS4 soon, due to the nature of my job I am unusure what other countries I may move to in the future so have always been concerned with region locking. So I just want to ask some questions before I get the PS4.

1. Are PS2 games locked on the PS4, for example could I play both a Japanese PS2 game on the PS4 and my old UK bought PS2 games on the PS4?

2. I am aware PS4 games are not region locked but online purchases are, would I be able to set up a UK account (I still have a UK bank card) and use it to buy DLC on games bought in HK (and around the world) as well as make purchases on the PSN store?

Thanks on anyone who can shine a light on the situation.