Google Drive and rclone
If your books are stored on Google Drive, you can use Plexdrive or rclone to make them accessible to Komga.
You will need to configure your library to force the directory modified time.
Rclone requires some specific configuration to cache files locally, and work better with Komga. Here is a user-provided configuration that works well (thanks Magikarp):
rclone mount <name>:<path> <mount_point/folder> \
--no-checksum \
--use-server-modtime \
--no-gzip-encoding \
--no-update-modtime \
--no-seek \
--modify-window 2m \
--allow-other \
--allow-non-empty \
--dir-cache-time 30m \
--cache-read-retries 15 \
--cache-db-purge \
--timeout 30m \
--vfs-cache-mode full \
--vfs-read-chunk-size 2M \
--vfs-read-chunk-size-limit 5M \
--vfs-cache-max-age 30m \
--attr-timeout 20s \
--poll-interval 9m \
--vfs-cache-poll-interval 10m