In Singing the Faith, for example, Wesley has 79 hymns and Watts, 13.
They have individual and distinctive styles – Watts being formal and somewhat distant while Wesley is more passionate, emotional and very much involved in what he writes.
You can see the difference if you compare these hymns –
Watts Let every mortal ear attend
And every heart rejoice.
The trumpet of the gospel sounds
With an inviting voice.
Wesley Come, sinners, to the gospel feast,
Let every soul be Jesu’s guest.
You need not one be left behind
For God has called all humankind.
Or
Wesley Christ, whose glory fills the skies,
Christ, the true the only light,
Sun of Righteousness arise,
Triumph o’er the shades of night;
Day-spring from on high, be near,
Day-spring , in my heart appear.
Watts Once more, my soul, the rising day
Salutes thy waking eyes.
Once more, my voice, thy tribute pay
To him that rolls the skies.
Dear God, let all my hours be thine
Whilst I enjoy the light,
Then shall sun in smiles decline
And bring a pleasing night.