By using variational quantum Monte Carlo techniques, we investigate the instauration of stripes (i.e., charge and spin inhomogeneities) in the Hubbard model on the square lattice at hole doping \delta=1/8δ=1/8, with both nearest- (tt) and next-nearest-neighbor hopping (t^\primet′). Stripes with different wavelengths \lambdaλ (denoting the periodicity of the charge inhomogeneity) and character (bond- or site-centered) are stabilized for sufficiently large values of the electron-electron interaction U/tU/t. The general trend is that \lambdaλ increases going from negative to positive values of t^\prime/tt′/t and decreases by increasing U/tU/t. In particular, the \lambda=8λ=8 stripe obtained for t^\prime=0t′=0 and U/t=8U/t=8 [L.F. Tocchio, A. Montorsi, and F. Becca, SciPost Phys. 21 (2019)] shrinks to \lambda=6λ=6 for U/t\gtrsim 10U/t≳10. For t^\prime/t<0t′/t<0, the stripe with \lambda=5λ=5 is found to be remarkably stable, while for t^\prime/t>0t′/t>0, stripes with wavelength \lambda=12λ=12 and \lambda=16λ=16 are also obtained. In all these cases, pair-pair correlations are highly suppressed with respect to the uniform state (obtained for large values of |t^\prime/t||t′/t|), suggesting that striped states are not superconducting at \delta=1/8δ=1/8.