It seems to have worked for you so far, I assume because your OneDrive setup is using a different account from your wife’s, so there is no sync duplication between the various computers - that is, Mylio and OneDrive do not both try to replicate the same images to the same computers (or at least, they haven’t so far).
If I understand things correctly then…
- You have both used your own OneDrive accounts to sync phone photos to your respective computers.
- You have used Mylio to organise these images as a single combined collection synced between the two computers and an external vault.
- Replacing your wife’s laptop introduces a difficulty, because both Mylio and OneDrive will want to sync the existing photos to the new one.
- You would prefer to continue using OneDrive rather than Mylio on the phone to collect new images. (Using Mylio on the phone would allow for a supported configuration on the laptop).
If all of this is right, it seems to me that you could separate the Mylio and OneDrive folders on the new laptop, and set OneDrive not to bring the existing images down, leaving it to Mylio to sync what needs to be there of the existing images for your wife’s use. Alternatively, you could set Mylio not to bring previews or originals to the laptop (it always has all thumbnails, but they are tiny), and let OneDrive bring the images instead. The choice between these two would depend on how your wife likes to access the photos on the laptop, either using Mylio or OneDrive, but not both.
Once all that is done, it seems to me that you could add the folder in OneDrive where new phone images turn up as an extra source folder in Mylio (if it is presently empty - I’ve assumed you move things elsewhere when they have been tagged, but if not then this won’t work), so that new phone images are added automatically, as you suggested above. This is unsupported as far as I can tell (I’m just another user of Mylio), but it would be no different from what has been happening before in your setup, where it seems to work because there is no duplication of replication - Mylio and OneDrive never end up arguing, as it were.
If it were me, I would take the external vault offline while doing any of this, so there is a copy in case things went wrong! The old laptop can also be left offline and untouched while this all happens.
In the end though, I would prefer to keep things entirely separate and fully supported - probably by using Mylio on the phone to collect new images itself. It would need you to run Mylio every so often on the phone so it would sync. Failing that, I would arrange an automated process on the relevant computer (such as a script file that runs in the background every so often) that picked up new images from OneDrive and moved them into Mylio’s Inbox or somewhere similar, so avoiding any possible clash over the managed folders between Mylio and OneDrive.
If you want a definitive answer, I suggest you contact Mylio support - they are really helpful, in my experience, and refer to this thread as you ask for their recommendation.