Congratulations on your admits!
I am no Masters expert but I would guess the HEC would be higher ranked.
I would consider where you want to recruit after graduating and what kind of work permit you are able to get. If you are not fluent in French and have no ability or desire to get there, your recruiting will be limited to the Netherlands, Ireland and possibly going to the UK but with the UK being out of EU, it will be tougher to recruit.
At the same time, if you have to pay more for Warwick, then it better I have some good hopes of recruiting. I doubt they would promise and guarantee it but hopefully jobs are available. At the same time you’ll be competing with higher ranked schools such as LSE and LBS... and also Oxford in Cambridge.
Unless you get a really good deal with the work permit and good chances of being hired at Warwick, I would probably start learning French.
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