You can use the suggested by my colleague localization approach with RESX files - Localizing Reports
. If you want to use a custom resource provider, you can test using user functions, which return the localized strings in the report.
Also note the report is data-driven, thus you can incorporate the localized strings with the actual data of the report and produce a localized data, that will be displayed in the report.
I hope the above information helps you.
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