data[W_, q_, {xmin_, xmax_, dx_}] := Thread[Table[
({x, #} &)  /@ Sort[ Eigenvalues[Energies[x, q, W]] ],
{x, xmin, xmax, dx}]];

Energies[_, _, x_, y_] := SparseArray[
  {Band[{1, 2}] -> Cos[x] Sin[y], Band[{2, 1}] -> Cos[x] Sin[y]}
  , {3, 3}]

Plot3D[Evaluate @ Sort @ Eigenvalues @ Energies[W, q, x, y]
  , {x, 0, 1}, {y, 0, 1}
  , PlotPoints -> 10]

data[W_, q_, {xmin_, xmax_, dx_}, {ymin_, ymax_, dy_}] := Transpose[
  Flatten[
   Table[
    {x, y, #} & /@ Sort[Eigenvalues[Energies[W, q, x, y]]]
    , {x, xmin, xmax, dx}
    , {y, ymin, ymax, dy}]
   , {1, 2}]
  , {2, 1}]

Energies[_, _, x_, y_] := RandomReal[{-x, y}, {3, 3}]

data1[W, q, {0, 1, 0.05}, {-3, 3, 0.1}]

ListPlot3D[ data1[W, q, {0, 1, 0.05}, {-3, 3, 0.1}] ]