I just did a sequencing test with the Godox (Cheetah, Adorama) 600BTTL. The A7RII is not a speed demon so this is probably not valid for sports shooters.
I always shoot uncompressed raw which limits buffer capacity in terms of shots in a burst. That's OK too, for me. My primary interest for this sort of thing is for getting some mild action from water skiers etc.
At low burst 4 lights kept up till the buffer was full at full power. At hi burst 4 lights kept up, with one miss, at 1/2 power. Two of the lights had batteries on them that had not been topped off since they arrived, so even though they showed full they may not have been as capability as they will be after being charged. It seems I've read that Lithium Ion batteries take a couple of charge cycles to reach full potential.
The half power also kept up at hi burst speed in HSS.
I'm not going to bother with uploading any pictures of Manny getting flashed. The only thing I was interested in determining was max power for the two burst modes on the A7RII. Getting the exposure right will depend on the shooting situation. The good news is that 1/2 power means a narrow beam reflectors means a reasonable light to subject distance is possible. Or being able to deal with the sun in a bright situation.