thankfully Chinese has always had a singular they, “他.”

for your convenience:

• 我: I, 我們: we
• 你: you, 妳: feminine you, 你們: plural you
• 他: he or sing. they, 她: she, 他們 plural they

by the way, 他 used to be he, she, or sing. they. the usage of 她 as she and 妳 as you (for females) is relatively recent. even now, you could replace all the ones with a “女” on its left with its “亻” counterpart and no one will say a thing. they are also pronounced identically.

I’m pretty sure plenty of singular theys have been invented in your language. It’s just that it’s not widely used at all and people would never understand you if you try to use it in a sentence.

not quite pertinent but you can have a gif as your avatar?

didn’t notice it lol