-------------------------------And it doesn't seem to mention anything about international loans. That's the hardest bit of info to find I've found.
V.7.5. the maximum number of Temporary Transfers to any one Club registrable in the same Season shall be four and in no circumstances shall more than one be from the same Transferor Club at any one time save there shall be excluded from these numbers any Temporary Transfer of the kind described in V.7.6.1 or V.7.6.2;
V.7.6. Not more than two Temporary Transfers shall be registered by a Club at the same time except that there shall be excluded from that number:
V.7.6.1. any Temporary Transfer which become permanent; and
V.7.6.2. the Temporary Transfer of a goalkeeper which in its absolute discretion the Board may allow in circumstances it considers to be exceptional;
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Reading that I'd guess the PL rules state it's 4 loans in over the course of a season with no more than 2 loan players registered at any one time and no more than 1 from the same club.
PL rules don't have to allow the maximum number of 6 allowed by FIFA or make specific rules for international loans. The PL just has to ensure their specific rules don't exceed FIFAs cap of 6 loans in total.