にしろ〜にしろWhether… or

Both list possibilities to show that no matter which is true, the conclusion holds. にしろ～にしろ is stronger and more emphatic, as in 行くにしろ行かないにしろ連絡して (Whether you go or not, contact me). にしても～にしても is more neutral, simply indicating that the result applies in either case, as in 大人にしても子供にしても楽しめる (Whether adults or children, they can enjoy it).

にせよ・にしろ follows a single phrase to mean even if (A), as in 値段が高いにしろ欲しい (Even if it’s expensive, I want it). にしろ～にしろ lists two alternatives to mean whether (A) or (B), as in 行くにしろ行かないにしろ連絡して (Whether you go or not, contact me).

Both list alternatives meaning whether (A) or (B), with the result unchanged. にしろ～にしろ is more common and conversational, as in 雨にしろ雪にしろ試合は行う (Whether rain or snow, the game will be held). であれ〜であれ is more formal, used in writing, as in 学生であれ教師であれ責任は同じだ (Whether student or teacher, the responsibility is the same).

にしろ～にしろ can follow verbs and broader phrases, as in 勉強するにしろ遊ぶにしろ全力でやれ (Whether you study or play, do it wholeheartedly). であれ follows nouns, な-adjectives, or wh-words and is more formal, as in どんな結果であれ受け入れるしかない (Whatever the result, we must accept it).

～ても～なくても and にしろ～にしろ can both mean 'whether it's (A) or (B)', but ～ても～なくても contrasts something with its negative, e.g. 食べても食べなくても ('whether you eat or not'), while にしろ～にしろ typically contrasts two opposing words or ideas, e.g. 勝つにしろ負けるにしろ ('whether we win or lose').

にしても and にしろ～にしろ are similar in that both express 'whether', but にしても tends to focus on a single case and convey contrast or concession, e.g. 遅れるにしても連絡はしてほしい ('Even if you're late, I want you to contact me'). にしろ～にしろ pairs two options and stresses that the result remains the same, e.g. 勝つにしろ負けるにしろ ('Whether we win or lose').

何しろ starts sentences with reasons, like after all. にしろ～にしろ lists two alternatives to stress the conclusion is unchanged, as in 行くにしろ行かないにしろ連絡して (Whether you go or not, let me know).

にしろ～にしろ lists alternatives where the outcome stays the same, as in 成功するにしろ失敗するにしろ挑戦する価値がある (Whether you succeed or fail, it’s worth trying). とはいえ acknowledges something but introduces a contrasting fact, as in 難しいとはいえ不可能ではない (That said, it’s not impossible).

〜でも〜でも and にしろ～にしろ both express 'whether it's (A) or (B)'. にしろ～にしろ sounds a bit more formal and hypothetical and works with a wider range of grammar, including verbs. Both forms show that the result or evaluation doesn't change regardless of the options given.

Both express the sense of 'whether', but in different ways. かどうか is used to present uncertainty, as in 面白いかどうか分からない ('I don't know whether or not it's interesting.'). にしろ～にしろ expresses that something applies regardless of the case, like 面白いにしろつまらないにしろ観たい ('Whether it's interesting or boring, I want to watch.').