Complex sentence: At E3 2017, Nintendo unveiled a new installment for the Nintendo Switch, tentatively named as "Kirby", and in September 2017, during a Nintendo Direct, Nintendo announced the official title "Kirby Star Allies" with a release date set for Spring 2018.
Split into simpler sentences: At E3 2017, Nintendo unveiled a new installment for the Nintendo Switch, tentatively named as "Kirby". In September 2017, during a Nintendo Direct, Nintendo announced the official title "Kirby Star Allies" with a release date set for Spring 2018.