Ah, I didn’t feel like she was particularly tsundere .She’s leaning on it, but not there yet. To be fair, she doesn’t know the MC: it is quite irritating if a random person walked to you and acted like they knew everything and treats you like a child. A great number of people would react to that, so her reaction was relatively realistic. It’s not like “she likes the MC yet is too shy about it so she acts mean”. He’s a stranger, she is getting to know about him, and finds slightly intriguing yet still more weirded out than anything.
I haven’t read the raws tho I can’t comment for future chapters.