The USB-C Specification specifies power delivery of up to 100W.
Increased power levels from existing USB standards up to 100W.
You won't be able to "daisy chain" or more technically charge MacBooks in series, charge MacBooks in series as 100W will be less than the required 174W (87W * 2). However, you will be able to charge them in parallel if your adapter has the capability to do so.