Although muslin quilts and swaddle blankets may both become useful baby essentials, they are designed differently.
A swaddle blanket is typically a lightweight single-layer fabric designed with enough flexibility and size for wrapping a young baby. A muslin quilt provides a more substantial layer and is better suited to appropriate everyday uses such as supervised play, cuddling and on-the-go comfort.
If you're specifically looking for a blanket for swaddling, choose a product designed for that purpose. For a cozy, versatile everyday blanket, a muslin baby quilt may be the better option.