\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) -2\,{a}^{2} \left ( y \left ( x \right ) \right ) ^{3}+2\,abxy \left ( x \right ) -b=0} \]
Mathematica: cpu = 3.346425 (sec), leaf count = 30 \[ \text {DSolve}\left [-2 a^2 y(x)^3+2 a b x y(x)-b+y''(x)=0,y(x),x\right ] \]
Maple: cpu = 0.234 (sec), leaf count = 0 \[ \text {could not solve} \]