Hypothetically speaking, if a rich overseas customer was willing to pay exorbitant amounts of money for it, and if the PLA is willing to allow AVIC/SAC to dedicate that amount of their aerospace resources for an overseas customer, then sure, the idea of a land variant of J-XY/35 being developed with an overseas customer being the launch export customer, is plausible.
It will be painful, expensive, and be a massive industrial undertaking for the export customer, but sure, it's "plausible".
But I think you are viewing this in a manner of "is it technically possible for the land based variant to be for export as a launch customer?" rather than "looking at the basis of evidence, rumours, and timelines, who is the launch customer likely to realistically be?".
Let's review what we know:
1. The land based variant is expected to make its maiden flight sometime this year in 2022, meaning its development should have been actively going on for the last two years or so, even as a derivative of the carrier based J-XY/35.
2. We do not have any evidence or rumours of any overseas customer being interested in properly pursuing the FC-31 or J-XY/35, or any derivative thereof, since it emerged, and certainly nothing of any sort of contract being signed. We do not have any Chinese language rumours to that effect either.
3. The land based variant of J-XY/35 has been rumoured to be intended for the PLA.
.... given the above, I don't think we can humour the idea that the expectd/imminent land based variant is for an export launch customer.
It just doesn't match any of the information that we have, which if anything is directly contradictory to the idea that it is for export.
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But let's be realistic.
No export customer is going to buy FC-31 or J-XY/35 variant as a lone launch customer, unless the PLA buys first. The costs and risks are just too high, and even oil rich countries in the Middle East know this.
If we want to talk about potential export prospects, the most likely path will be a dedicated export cleared variant of the land based J-XY/35 variant after the PLA has bought it and already operates it.
Export customers will be able to take advantage of a product whose development that the PLA has already paid for, with the risks already accounted for, and with an expansive logistics and support network to be able to have their own aircraft leverage off.
None of the industrial risk, and no upfront developmental costs -- only procurement and sustainment costs, which is what most nations want.
Perhaps if you were a nation that wanted to rapidly advance your aerospace industry to be able to produce 5th generation aircraft, then perhaps it would make sense.... but even then, why wouldn't you simply wait for the PLA to buy the land based J-XY/35 variant first, and then express an interest in buying it with co-production and a degree of transfer of technology? Why embark on the additional risk and cost of trying to be the launch customer for a new variant of an aircraft?
(Hint, this is the major reason why the F/A-18L -- the land based variant of the F/A-18A -- never hooked a customer, because no prospective export customer wanted to be the one to front up the costs and risk of developing a new variant, and because Northrop themselves weren't willing to front up the costs, and the US was not buying the F/A-18L either. With no one willing to pay for the full scale development of the aircraft, it simply withered and disappeared, and even customers interested in the F/A-18L proposal simply bought the lower risk F/A-18A with minimal or no modifications from the standard USN version, retaining the folding wings, reinforced structure and landing gear and everything else)
Adapting my previous overview, it would look like this (green, bottom right corner):
View attachment 86547
