Merging DADA2 feature-tables. What about likely duplicate features in different tables?

Thank you guys!
I am still a bit confused here: a given ASV will likely have the same hash id even though it came from different sequencing runs, right? Given that the lenght, primer etc are the same… Which means DADA2 somehow use sequence composition to assign a hash id and “knows” which hash id to assign? (my interpretation, but should come back to dada paper and read a lot more)

I am fine if MD5 hash is almost always unique, so I could just merge the tables setting any of the --overlap-methods, given that my sample IDs are unique and hash ids are likelly unique. I’ll then get a table where ASVs tend to not be repeated, in terms of DNA sequence.
Is that right?