Locus Map imports GPX, points included, so a Google Maps list takes a few steps to load. Paste your shared list link into the converter above and export as GPX. Put the file on your phone before you start.
Import the GPX in Locus Map
Open the main menu, tap the more functions icon, and choose Import. Locus opens its own file browser. Files it can import show in full color. Pick your GPX, then choose the folder the points should go in.
You can also start from Points, tap the add icon, and choose Import. Or open a folder's own menu and choose Import to send the points straight into that folder.
Options on the import screen
The import screen lets you delete the other points in the folder first, preview the points without saving them, show them on the map after the import, and update elevation when you have offline elevation data. Leave the delete option off unless you want to replace what's already in that folder.
Not sure Locus is the right offline app? The Organic Maps page covers a free alternative that takes the same GPX file.