それにY, Además, Asimismo

なお② and それに both add information, but differ in tone. それに is neutral and used in everyday speech. なお② is formal and often written, with a tone of explanation or emphasis, e.g. 商品の仕様は変更される場合があります。なお、返品はできません ('The product specifications may be changed. Furthermore, returns are not accepted.').

それに and その上 both add information. それに is neutral and casual. その上 has a slightly more formal tone and implies building upon the previous statement, e.g. 彼は優秀だ。その上、性格もいい ('He's capable, and what's more, he's kind too.').

それに and おまけに both add information. それに is neutral and just adds a point that logically follows. おまけに adds something extra or unexpected, often with a tone of surprise or bonus, e.g. おいしかったし、おまけに安かった ('It was delicious, and cheap too!').

それに and しかも both add information, but しかも is stronger. それに is neutral: it adds a point that logically follows. しかも emphasizes what comes next, like 'what's more' or 'on top of that', e.g. 安い。それに美味しい。しかも体にいい ('It's cheap. And tasty. And what's more, it's good for your body.').

Both それに and また can be used to provide added information, like the English 'in addition' or 'moreover', but with slightly different nuances. また has a slightly formal tone, and adds information in a neutral sense. それに is more colloquial and has the nuance of adding information that supports or reinforces the previous statement.

すると and それに are both sentence starters but differ in usage. すると shows result or reaction, e.g. 雨が降った。すると傘を差した ('It started raining. Then he opened an umbrella.'). それに is additive and neutral: 雨が降っていた。それに寒かった ('It was raining. And cold too.').