I've been looking at song books at Derry's central library today. Two of them gave English translations for SWliabh na mBan.
Follow the link given on this thread on 3 Jun for Songs of 1798. When you get there, scroll down a few songs and you'll see "Sliabh na mBan".
The English translations are for two verses,the one that begins "Is oth liom féinig" (v. #2) and "Tá an Francach faobhrach" (v #7)

from Mary O'Hara "A Song for Ireland". London:Michael Joseph,1982:
I dread the thought of the day's defeat
When the Gaels were slaughtered
For the invaders are mocking us
Claiming that they don't fear our lances or pikes.
To start with, our leader failed to turn up and we were unprepared in disarray
Driven like cattle without cowherd
On the sunny slopes of Sliabh na mBan

The eager French are ready in their ships
Tall masts sailing at sea for some time now
It is rumoured that they're heading for Irleand
To restore their rights to the unfortunate Gael.
If I thought that such a story was true,
My heart would be as light as a blackbird on the thorn.
That invaders would be vanquished and the horn would sound once more
On the sunny slopes of Sliabh na mBan

From Dominic Behan. "Ireland Sings". Essex Music, 1973 (distributed by Music Sales Corp) Singable (with tune simplified a little bit)translation by Wolfe Stephens (c 1965, Coda Music)

My heart it is broken
in sorrow a token
of regret for jeers now spoken by the English lords
They knew we could do no harm for they knew we posses'd no arms
But forks and pikes and but a handful of rusted swords.
We had no major, mo hero leader,
No man to order us we drifted on
Like cows to a drover e'er the fair day is over
We scattered on the sunny shoulders of Sliabh na mBan

But the French are waiting
Their masts are straining
And people they are saying they sail the sea
With their ships all in serried lines and their order is grand and fine
And they race against the wind to set old Irleand free.
Now if I knew this tale was true
I'd sing like the blackbird for you a happy song.
To see broken ranks swinging and hear French trumpets ringing
as Freedom they come bringing to Sliabh na mBan

The notes in the Behan book incorrectly translate Sliabh na mBan as the white mountain instaid of as the mountain of the women. Can anybody tell us more about "Wolfe Stephens" or another translator in the book, "Fintan Connolly"? I do suspect that these are pen names based on heroes such as Fintan Lawlor, James Connolly, Wolfe Tone, James Stephens???