としてもEven if (we assume), Assuming, Also as

にしても and としても both mean 'even if', but にしても can introduce a judgment that doesn't directly follow from the condition, e.g. 行くにしても不安だ ('Even if I go, I'm uneasy'). としても implies that the result stems logically from the assumption, e.g. 行くとしても一度だけだ ('Even if I go, it'll be only once').

Both express hypothetical conditions, but with different implications. たとえ〜ても presents contrast, like 'Even if (A), still (B)', e.g. たとえ雨が降っても行きます 'Even if it rains, I'll go.' としても assumes (A) as a premise for argument or stance, e.g. 行くとしても一人では行かない 'Even if I go, I won't go alone.'

としたら・とすれば・とすると and としても both introduce hypothetical situations. The former typically presents a scenario as worth considering, e.g. 留学するとしたら ('If I were to study abroad'). The latter introduces an unlikely or extreme case and implies that something will happen regardless, e.g. 行くとしても一人では行かない ('Even if I go, I won't go alone').

Both forms can express the meaning of 'even if' or 'even though.' ても is more versatile and commonly appears in expressions like てもいい 'it's okay to (A)' to ask or give permission. としても has a stronger hypothetical nuance similar to 'Even assuming that…', and can also serve as a more emphatic version of として. For example, 私としても大変だ ('It's tough even for me.').