\[ y'(x)=\frac {\sin \left (\frac {y(x)}{x}\right ) \csc \left (\frac {y(x)}{2 x}\right ) \sec \left (\frac {y(x)}{2 x}\right ) \left (2 x^2 \sin \left (\frac {y(x)}{2 x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+y(x)\right )}{2 x} \] ✓ Mathematica : cpu = 0.0736799 (sec), leaf count = 30
DSolve[Derivative[1][y][x] == (Csc[y[x]/(2*x)]*Sec[y[x]/(2*x)]*Sin[y[x]/x]*(2*x^2*Cos[y[x]/(2*x)]*Sin[y[x]/(2*x)] + y[x]))/(2*x),y[x],x]
\[\{\{y(x)\to -x \arccos (-\tanh (x+c_1))\},\{y(x)\to x \arccos (-\tanh (x+c_1))\}\}\] ✓ Maple : cpu = 0.166 (sec), leaf count = 51
dsolve(diff(y(x),x) = 1/2*sin(y(x)/x)*(y(x)+2*x^2*sin(1/2*y(x)/x)*cos(1/2*y(x)/x))/sin(1/2*y(x)/x)/x/cos(1/2*y(x)/x),y(x))
\[y \left (x \right ) = \arctan \left (\frac {2 \,{\mathrm e}^{-x}}{c_{1} \left (\frac {{\mathrm e}^{-2 x}}{c_{1}^{2}}+1\right )}, \frac {\frac {{\mathrm e}^{-2 x}}{c_{1}^{2}}-1}{\frac {{\mathrm e}^{-2 x}}{c_{1}^{2}}+1}\right ) x\]