After some research, I’ve found out that Logseq doesn’t have a webdav integration for Android (which prevent syncing with Nextcloud directly). Here is a related thread to nextcloud integration.
For WebDav Integration, magisk rclone could be a solution for rooted android device, allowing to edit files on the cloud directly. I tried it, but I wasn’t able to set it up properly. This is not a userfriendly solution.
There’s also a tricky way to sync logseq with nextcloud, but it needs to be sync (download) manually to the android device (uploads are automatic). Here is how, better feature might come later.