NOT Tested: Copy to new
\,\s(weight:.+?)\,*
Replace: \1
Destination field : <your other column> <<<this is important or you will lose the rest of the tags
Search for a comma Space
Capture weight an up, but not including a comma (optional)
The cleanup is a whole lot trickier
AND SERIOUSLY NOT TESTED Make a Backup, there is no Undo
I would do as 2 steps
First is where Weigh is the last item (this should just truncate it away)
(.+)\,\sweight:.+?
Replace:\1
Second is similar, but carves out weight and puts the 2 chunks together with a comma space
(.+)\,\sweight:.+?\,\s(.+)
Replace:\1, \2
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