\[ y'(x)=\frac {y(x) \left (-a x \log (y(x))+x^2+y(x)\right )}{x (a x-y(x)-y(x) \log (x)-y(x) \log (y(x)))} \] ✓ Mathematica : cpu = 0.403023 (sec), leaf count = 33
DSolve[Derivative[1][y][x] == (y[x]*(x^2 - a*x*Log[y[x]] + y[x]))/(x*(a*x - y[x] - Log[x]*y[x] - Log[y[x]]*y[x])),y[x],x]
\[\text {Solve}\left [a x \log (y(x))-\frac {x^2}{2}-y(x) \log (x)-y(x) \log (y(x))=c_1,y(x)\right ]\] ✓ Maple : cpu = 0.496 (sec), leaf count = 31
dsolve(diff(y(x),x) = (y(x)-a*ln(y(x))*x+x^2)/(-y(x)*ln(y(x))-y(x)*ln(x)-y(x)+a*x)*y(x)/x,y(x))
\[y \left (x \right ) = {\mathrm e}^{\operatorname {RootOf}\left (2 a \textit {\_Z} x -2 \,{\mathrm e}^{\textit {\_Z}} \ln \left (x \right )-2 \textit {\_Z} \,{\mathrm e}^{\textit {\_Z}}-x^{2}+2 c_{1}\right )}\]