You can continue to use the ‘purchase’ event to track the products sales on your ‘shop.domain.org’. For the donations received on ‘give.domain.org’, stick with the custom ‘donate’ event. The reason your revenue or ‘value’ metrics might not be showing up on GA4 is because GA4 treats custom events a little differently. You will need to register ‘value’ as a custom metric in GA4. In the GA4 interface, go to ‘Custom Definitions’ and then to ‘Create Custom Metrics’. Here you can name your custom metric (like Donation Value), choose the scope as ‘Event’ and select your custom event (‘donate’). Once GA4 recognises ‘value’ as a custom metric, you should be able to see the tracked donations under Event data in your GA4 reports. It might take a while for the metric to reflect in your report. This way, you’ll be able to track both donations and product sales separately and effectively.