Ever since I saw Brooke playing this live and noticed that she was playing it
differently to what I had learned it bothered me, and one day (I can't remember 
how, I think I was just browsing Youtube) I found this video of a guy who showed 
how to play it like she does. The E used (I looked this up to check the actual 
name of the chords) isn't the same as the one I found which was pretty much an Em 
with the e, B and G strings blocked, and technically it is just another way of 
playing E as it uses the same notes, but it's played like a power chord would 
usually be played. I wasn't sure about the G#5 or the F#5 so I just wrote them as 
fifths since power chords seem to have a habit of that.
So here it is, Hosanna in power chords. Thanks to Jon Fletcher (who I learned it from) :]

Chords used:
C#5:e 0  E: e0 (022000@1) A5: e0 (022000@1) B5: e0 (022000@1) G#5: e0 (022000@1) F#5e 0
    B0 (x2444x@1)    B0 (x2444x@1)     B0 (x2444x@1)     B0 (x2444x@1)      B0 (x2444x@1)     B0 (x2444x@1)    G6 (320003@1)    G9 (320003@1)     G3 (320003@1)     G4 (320003@1)      G4 (320003@1)     G2 (320003@1)    D6 (xx0232@1)    D9 (xx0232@1)     D2 (xx0232@1)     D4 (xx0232@1)      D6 (xx0232@1)     D4 (xx0232@1)    A4 (x02220@1)    A7 (x02220@1)     A0 (x02220@1)     A2 (x02220@1)      A6 (x02220@1)     A4 (x02220@1)    E0 (022100@1)    E0 (022100@1)     E0 (022100@1)     E0 (022100@1)      E0 (022100@1)     E0 (022100@1)

Intro: C#5  E  F#5  G#5 x2

[Verse one:]
EI (022100@1)see the king of glory
C#5Coming (x133xx@4)on the clouds with fire
                 A5 (x022xx@1)                     B5 (x244xx@1)   C#5 (x133xx@4)
The whole earth shakes, the whole earth shakes
EI (022100@1)see his love and mercy
C#5Washing (x133xx@4)over all our sin
            A5 (x022xx@1)             B5The (x244xx@1)people sing, the people sing


[Chorus:]
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       C#5B5
Hosanna in the highest
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       B5 (x244xx@1)C#5Hosanna (x133xx@4)in the highest


[Verse two:]
EI (022100@1)see a generation
C#5Rising (x133xx@4)up to take the place
               A5 (x022xx@1)                 B5With (x244xx@1)selfless faith, with selfless faith
EI (022100@1)see a new revival
C#5Stirring (x133xx@4)as we pray and seek
              A5 (x022xx@1)               B5We're (x244xx@1)on our knees, we're on our knees

[Chorus:]
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       C#5B5
Hosanna in the highest
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       B5 (x244xx@1)C#5 (x133xx@4)E (022100@1)F#5 (244xxx@1)G#5Hosanna (133xxx@4)in the highest

C#5  E  F#5  G#5

[Bridge:]
A5 (x022xx@1)                       B5Heal (x244xx@1)my heart and make it clean
E (022100@1)                     C#5Open (x133xx@4)up my eyes to the things unseen
A5 (x022xx@1)                     B5 (x244xx@1)               C#5Show (x133xx@4)me how to love like you have loved me
A5 (x022xx@1)                            B5Break (x244xx@1)my heart for what breaks yours
E (022100@1)                       C#5Everything (x133xx@4)I am for your kingdom's cause
A5 (x022xx@1)                 B5 (x244xx@1)  C#5As (x133xx@4)I walk from earth into eternity


[Chorus:]
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       C#5B5
Hosanna in the highest
C#5 A5    B5 C#5
Hosanna, hosanna
    A5 (x022xx@1)       B5 (x244xx@1) C#5Hosanna (x133xx@4)in the highest
    A5 (x022xx@1)       B5 (x244xx@1)EHosanna (022100@1)in the highest