Disclaimer: Doesn't work with TraditionalForm
list = Table[PolynomialQuotient[x^n - a^n, x - a, x], {n, 2, 12}]; ClearAttributes[{Plus, Times}, Orderless] list /. Plus[a{h_[a, x] :> Plus[xh[x, a] /. Times[a, x] :> Times[x, a] /. t : Times[Power[a, i_], Power[x, j_]] :> Times[Power[x, j], Power[aReverse@t, i]] /. t : Times[a, Power[x, j_]] :> Times[Power[x, j]Reverse@t, a] /. t : Times[Power[a, i_], x] :> Times[x, Power[a, i]]Reverse@t} /. Plus[a : Plus[Power[aPower[a, i_], m__b__, c : Power[x, j_]] :> Plus[Power[x, j], mPlus[c, Power[ab, i]]a] // Column Don't forget
SetAttributes[{Plus, Times}, Orderless] 