We can already figure much of that out from the technological specifications of the F-35. Simply looking at the capabilities can give us strong clues on how to neuter or at least limit the inherent F-35 advantages from a tech standpoint.
The rest of that comes down to how the pilot behaves, and what tactics they have been trained in. And this is where differences in training, corps attitudes, and even pilot personalities can dramatically affect performance.
And while I fully agree with you in regards to pilot training, our problem is that a Canadian fighter pilot is likely to behave (tactic chain, decision trees, emotional responses, etc.) considerably differently than an American fighter pilot. As such, while we need to train our pilots in Gripen jets against F-35 jets in combat-like scenarios, we need to do so against American pilots, not Canadian ones.
And that’s the tough part - how do we get the American administration to willingly play along with activities that are obviously meant to train our pilots to fight theirs, and gain a consistent toehold against pilots in F-35s even if it means losing a few Gripens for every one of their F-35s. It needs to be done with a great deal of subtlety and subterfuge.

The objective is not to win. Winning against America’s imperial might is impossible.
The objective is to make them bleed as much as possible. To make victory as phyrric and as painful for them as possible. And when going up against the most expensive war plane in human history, this means choosing the aircraft that can get as technologically close as possible with as many units as possible on a per-dollar-spent basis.
We can make them bleed much more with 420 fully-functional Gripens than we can with 88 partially-functional F-35s that can be remotely shut down against our will.