(Disclaimer the beginning part before 1.2.3. is all by ear because it's not in the lyrics and is also only in the sekai ver.)

"Are you all ready?"
"Naturally!"
"I hope everyone smiles!!"
"Fufu. Then, here we go. On the count of three..."
"Wonderhoi!!!!"

1.2.3
I found them! These precious feelings I want to stay with me
I've got to hold them close, or else they'll fall out of my grasp
You've got to put your heart on fully display without shame, right?
See, see, I want to play the notes of this emotion, more and more
Hurry! Hurry! When? When? Right away!

What do you want to do? and what do you like? Showtime! Showtime!
What do you want to be? ...? Ooh... Wonderhoi!!!!"

What I want to express is a melody that can't be said in only words
But using this overflowing rhythm, it should be fine (your own rhythm's more than enough!)
Listen closely, and if the beat of your dream's picked up,
Let's dance!! Yeah!! (tarara)
Let's sing a song!! (shalala)
Ah~
(Wonderlands x Showtime!)

Glory! Living's the best! I want to sing! (I want to sing!)
More? (More!)
Dream more and more! Like the thing you'd see in a colorful world
Steady! Steady! Step by step, let's more forward
Wake up! (Wake up!)
Stand up! (Stand up!)
Aim for the self you want to become, and Go! (Go!)
Let this song filled with desires resonate!
Glory Steady Go!

It's time to smile! (fufu...)
It's time to oooh... WAO!!!
It's time to showtime!
Wonderlands x Showtime

Lalala~
Wonderlands x Showtime

I'll do it again! These feelings that're so good at playing hide-and-seek
Come from a place of soft smiles, isn't that right?
I've always thought, this isn't something I want to forget
See, see, I really, really do want to draw up this dream!
Hurry! Hurry! When? When? Right away!

What do you want to do? and what do you like? Showtime! Showtime!
What song do you sing? ...Lalalalalalala

And basically, that's a melody that can't be formed any time but now
With a precious, 1.2.Jump! (Jump with your own rhythm!)
Weave together the wing, and if your own blue spring's burst forth
Let's dance!! Yeah!! (tarara)
Let's sing a song!! (shalala)
Ah~
It's show time!

Glory! Living's the best! I want to dance! (I want to dance!)
More? (More!)
Smile even more! Sort of like the thing you'd see in a sparkling future
Steady! Steady! Even when rain's falling, let's steadly go forward
Wake up! (Wake up!)
Stand up! (Stand up!)
The steps you've taken up to now won't disappear
If you look up to the sky, a rainbow will form
So don't worry!!

Carve your path, Shake! Shake! Shake!
Let it resonate, clap your hands!
Even if it's a clumsy sort of sound, I want to convey it
This ordinary daily life
Are shiny days
Ah, these tears are going to spill...

Let's dance!! Yeah!! (Tarara)
Let's sing a song! (shalala)
Ah~
Wonderlands x Showtime!

Glory! Living's the best! I want to sing, ah!
More? (More!)
Dream more and more! 'Cause I'm finally that sort of diva I looked up to
Steady! Steady! Step by step, let's more forward
Wake up! (Wake up!)
Stand up! (Stand up!)
Aim for the self you want to become, and Go! (Go!)
Let this song filled with desires resonate!
Glory Steady Go!

It's time to smile! (fufu...)
It's time to oooh... WAO!!!
It's time to showtime!
Wonderlands x Showtime
Yay

translation notes:
During each chorus the name of one of the sega vocaloid rhythm games is said (in order: sekai (world), mirai (future), diva)
the line about "blue spring" is a pun i've seen a lot because the kanji for "youth" can also be read as "blue spring". i decided to translate it directly but it's basically also saying youth in that line