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It doesn't really work that way...

Simply put - all the parts need to support 7.5W wireless charging. The charging brick, the cable, the wireless charger and the phone. In your case your charger doesn't. So you can connect it to a 87W Macbook charger and it will still charge with 5W.

This is intentionally... for so nothing bad happens to your battery.
 
The wireless charger says it supports fast charging so I’m not sure if only with a certain power puck and cable? It didn’t come with one and can’t find any info on it
 
Well, wireless charging appears to still be a rather wild wild west. Apparently Apple supports only Belkin and Mophie to deliver 7.5W. Everything else stays at 5W, no matter what is written anywhere.
 
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