I am using Syncthing with a vault between windows and android over Wifi. (BTW: location services to detect the wifi name takes a lot of battery, is there a way to get them without it?)
I get conflict files.
As I understand it, syncthing works on file level, not content level, ie it looks for differences in size, change date, maybe other metadata.
Given that differences in obsidian mean addition and removal of text within the file and the right thing to do is to look at the newest file and merge both, not copy the newest file to the other device and overwrite.
Keep in mind that if the action is to “look at the newest file and merge both”, the end result will be that any text that was removed in the newest version of the file – but still exists in the older version – will be effectively undeleted. For a note taking app such as Obsidian, it’s likely not what most users would want/expect to happen.
What you need is a revision control tool. Search online for “git sync obsidian” for tips on using Git (which has a merge feature).