Conditional formatting in bulk (or formatting painter)

Hi, RMDNA 

According to your description, you would like to find a feature in PowerBI similar to the formatting brush in Excel for easy formatting, unfortunately, as of the current version, Power BI does not have a feature similar to the Excel formatting brush. You can submit an idea for here and the product team will take note of such a need.

Related Link: New tab (powerbi.com)

However, you can try the following workaround:

1.DAX Metrics, If you use DAX metrics for conditional formatting, you can create a metric and reference it in the conditional formatting dialog box for each field. This way, you only need to adjust the metric if the rule needs to be changed, and it will be reflected in all fields that use the metric.
Tips for speeding up the process:
2.Templates, If you frequently use the same conditional formatting rules, consider creating Power BI templates. Once you have set up your report with all the formatting, you can save it as a template and then use this template to launch a new report with the existing formatting. 
3.Power BI Template (.pbit), If you are launching a new report, you can save time by using a saved template with conditional formatting already applied.

Best Regards,
Yang
Community Support Team

If there is any post helps, then please consider Accept it as the solution  to help the other members find it more quickly.
If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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