Replace multicam clips in timeline, with other multi cams?

I've got various edits which have been done in one older library, which I've moved into another new library. The edits and clips come across fine, but the multi cam (interviews)  are now duplicated in the library. As I've been doing LOTS of metadata tagging on the new multicam clips in the new library, I'd like to replace the older multi cams which are on the timeline, with the newer ones, so the index has all the new metadata and then delete the old ones - to keep the library clean. But, a drag and drop replace doesn't work, nor does replace from start or end etc. The only way I could get this to work is to manually create the in point on each new multicam for each cut (for 20 min docs... not nice) and then drag each new multicam onto each old multicam in the timeline one by one. There must be a better way?

As far as I know only the 'Merge' app, now an extension as part of Postlab ( hedge.video/postlab ) can do this.
You could also try to use the 'MergeX' app that is still available on the App Store but is not supported anymore.

I haven't tried it and don't know if it's possible and if it is, whether it's more tweaky than you're comfortable with and/or more work than just re-editing by hand, but I wonder if exporting XMLs of the projects containing the old multicams and the new multicams and then editing the old multicam XML text so the clips reference the new multicams. I'm thinking a Find and Replace for each mc-angle name and angleID. Then import that XML.

Thanks for this - it does sound a bit tweaky for me but I’d it works it would save me a lot of work. I love all the meta data tagging but I’m finding this process pretty painful as I’ve done so much work.

I may try using merge to copy all the meta data from the mew MCs to the old (which are in the timeline) and see if that works but being able to replace (like precomps in after effects) would be best.

Only problem with Merge is that it creates yet another nulticam rather than overwriting the one that's in the current timeline, so I'm back to square one....

I haven’t used Merge much but isn’t that the idea that it  creates a new timeline with new clips with the merged data? Anyway I think being able to copy keyword or ratings ranges based on TC would be a fantastic feature to have. 

Yeah, sadly it doesn't work as it creates new MCs and then I'd have to manually replace those anyway. Darn!!!