Like [Artificial (Other)] (qaa)
Like [Multiple languages] (mul)
Like Work language [No lyrics] (same zxx)

As it is not a language name:

• it should be shown as [No linguistic content] and
• not appear alphabetically between Niuean and Nogai

In works, [No lyrics] (zxx) is in Frequently used.
In releases it should probably stay in Others, as [No linguistic content], after (alphabetically) [Artificial (Other)].