I have a challenge, can you distinguish which character set/s belongs to Japanese & Mandarin?
There are of course differences between Kanji / Hanzi but the “difficult” part is knowing which language is which simply by glancing (unless you know either 日本語 or 中文 that is).
In contrast, do you know any words that are near identical when written down between two “alphabetical” languages based on their spelling?
As someone who cannot read either language, I normally go by the rule of thumb that if it has a lot of curves it is probably Japanese, otherwise I assume it is Chinese. If we can throw Korean into the mix then I just need to see one circle and that’s how I determine if it is or not. It’s not a perfect system, but I would surmise that I can guess the language well above half of the time.
Also aren’t the characters for Chinese shared across all spoken versions, if so, why did you specify Mandarin instead of just saying Chinese?
In Hong Kong, Macau (both speak majorly Cantonese), and Taiwan (mostly speaking their own flavour of Mandarin, Hokkien, and a few other ones too depending on where you are), they use traditional Chinese characters while the mainland PRC (huge pot of all sorts of dialects and other bits, but Mandarin is the standard language) is simplified, and somebody who knows one is not always able to read the other.