The information about this Juechen Princess is quite scarce.
She is usually very low-key, unlike other princesses who enjoy socializing. Her last visit to Country A was her only relatively high-profile social event.
At that time, Juechen Princess deliberately overshadowed Xia Yanyan, obviously with the intention of outshining Country A's national treasure and setting the stage for the once-every-twenty-years Nautical Battle rivalry. Unfortunately, her plan was thwarted by Ye Xingguang, and she couldn't secure a prelude of victory.
It's understandable how upset Juechen Princess was back then, otherwise she wouldn't have issued a challenge now. It's likely that over the past half-year, she has been rigorously honing her singing skills, confident that she can outperform in that area.
Very quickly, domestic netizens learned of this matter: the K country's Juechen Princess challenged the nation's new national treasure Xia Qiongqiong.