Oxford united will lose their ground in a year or two, is there anywhere close that could groundshare with them?
Yes, if Oxford United really did lose the Kassam Stadium and the new stadium failed, there are a few possible groundshare options — but none are particularly attractive. Their geography makes it awkward because they are fairly isolated from other EFL clubs. Their Kassam licence situation is the issue: the current arrangement is only a short-term solution and the club has said it needs a permanent home.
The realistic options would probably be:



Probably the most logical footballing option.
Problems:
This would probably be the EFL's preferred sort of solution.
The traditional rival option.
The issue is obvious: Oxford and Swindon have one of the nastier rivalries outside the top divisions. A temporary move there would be hugely controversial.
It would be like Sheffield Wednesday having to share with Sheffield United — possible in an emergency, but nobody would enjoy it.
Actually quite plausible geographically.
Problems:
A longer shot.
But it is probably too far.
Technically, maybe:
But a League One/Championship club would need substantial upgrades, especially around:
The irony is that Oxford's best temporary option is probably the thing they are trying hardest to avoid: remaining tenants at the Kassam. The club's own argument is that without the new stadium they have no long-term future, because the current ground is not theirs.
Given Oxford's location, I think they are one of the few EFL clubs where losing their ground really would create a genuine crisis rather than just an inconvenience.