This situation is like the Ivory Coast/Côte d’Ivoire. It's just Swaziland's name in their own language. Just like Germany is Deutschland, Mongolia is Монгол Улс, North Korea is 조선민주주의인민공화국 and Myanmar is ပြည်ထောင်စုသမ္မတ မြန်မာနိုင်ငံတော်. I have used all these names interchangeably.