So I'm not really into CW but I get vouchers from my subscription. Can I buy CW with my voucher and sell/give them away or are they account locked?

The CW themselves are not account locked so you can sell them! It's fairly common for people to list their vouchers for sale on the r200 sale forum. The buyer will tell you the CW they want that's in the shops and you'll buy it and place it in trades where they can offer CSC or sP for it. The vouchers themselves can't be traded.

@Last_Chance Awesome!! Thank you so much! I'm really happy to hear that so they don't go to waste in my account.