Unless you add the report as an inline search (or the report generates a lookup via outputlookup), what you’re describing isn’t possible.
If you add it as an inline search, you’re back to your initial problem of needing to update it each inline search use as well as the original report
I often make use of scheduled reports to create lookup tables, though (for performance reasons). If you do that, then you can just reference the lookup table on your dashboard, and do with it whatever you want like any other lookup table:
| inputlookup mylookup.csv
| stats count
Or
| inputlookup mylookup.csv
| stats count by system
Etc
If you want to add summary data to the stats table on the dashboard, format the visualization and add totals:
from User warren – Stack Overflow https://stackoverflow.com/questions/68468069/it-is-possible-to-modify-already-existing-report-within-splunk-dashboard/68470879#68470879
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