Comparison between the stellar, l _⋆, and molecular, l _mol, scale lengths, computed by fitting exponential profiles to the respective surface densities as a function of galactocentric radius. Blue circles and green triangles correspond to 23 ACA EDGE galaxies with Σ_mol > 1 M _⊙ pc⁻² for all the annuli within 1 kpc. The blue solid line is the best fit for the model y = α x for the main sequence, omitting galaxies with low-quality l _mol fits (light-colored symbols). The gray dotted and orange dashed–dotted lines are the best-fit relation for CARMA EDGE (Villanueva et al. 2021) and VERTICO (Villanueva et al. 2022), respectively. The shaded gray area corresponds to the median physical resolution of ACA EDGE galaxies. On average, the figure shows a ∼6:5 relation between the molecular and stellar scale lengths.