The above answerAllan's answer is not correct, I was able to daisy chain my Mac. I am currently at a conference without my charger and I have daisy chained my Mac to another Mac (both USB-C 2017 Mac Book Pros). Both Mac's are closed, so there is not much variance in usage as both are idle. I opened the screens and checked the power level on both every 10 minutes. The second Mac charged much slower and seemed to charge faster once the first Mac was fully charged, but it still seemed slower than normal to charge.
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| Time | Mac 1 | Mac 2 |
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| 0 mins | 81% | 22% |
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| 10 mins | 89% | 24% |
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| 20 mins | 96% | 26% |
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| 30 mins | 100% | 29% |
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| 40 mins | 100% | 33% |
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| 50 mins | 100% | 37% |
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| 60 mins | 100% | 42% |
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