I know if you have the Team Versioning option, you can do a deployment group of just the Sequence Generators and one of the options is to keep the current values or overwrite the current values in the target repository. But you wouldn't be able to deploy between 9.1 and 9.6 repositories.
You might be able to export the Sequence Generators to XML and import them into the 9.6 repository. That should work. I was able to do something similar between 9.1 and 10.1 repositories.
PowerCenter 10.1 on Windows 2012
PowerExchange for LDAP
PowerExchange for SAP Netweaver
You can use the command-line utility "pmrep" with its function "UpdateSeqGenVals" to update one single Sequence Generator. So you might want to extract all SEQ from your repository using a query or via the Metadata Exchange view REP_ALL_TRANSFORMATIONS and then construct a batch file / script from these data to update each single SEQ. That's the cleanest way to do it.
Sorry, forgot to add that the REP_ALL_TRANSFORMS view (REP_ALL_TRANSFORMATIONS was a typo) does not give the current and max value of a SEQ and so on. You have to extract these details from the view REP_WIDGET_ATTR for the Sequence Generator transformations you've found in REP_ALL_TRANSFORMS.
Informatica provides metaquery tool, which connect to PowerCenter Tool and gets important metadata information including the Sequence Generator.
You can find MetaQuery details here: