If you need the folder to remain as a single compressed file (ZIP), use a mobile browser like Chrome.
For users who want an actual .zip file of their folder saved to their phone's storage (similar to how it works on a PC), there is a trick. google drive download folder android
To download a Google Drive folder on Android, you can use the official app to make files available offline, use the "Desktop Site" trick in a browser for a direct ZIP download, or use a file manager for local copying. If you need the folder to remain as