Re: 2 years?
Indeed, the UK has almost no cards and N.I. will be destroyed by a hard border, the first ever. Gibraltar will become unemployed and economic collapse as Spain will close border.
Scotland has no say and can do nothing unless they leave UK (which will seriously upset the Spanish till it's pointed out that Scotland is not England and was only part of Great Britain from maybe 1707). So no EU deal for an Independent Scotland till Spain calms down (or possibly Catalonia leaves Spain, who knows what that would trigger?). Anyway why is Spain holding bits of North Africa?
It won't be marvellous for Ireland in short term but in longer term better as too many Irish Imports are via UK middle men creaming off a percent (likely goes back to Victorian Era in some cases). Certain agriculture aspects of Ireland will be hit worst.
It's a disaster, but at the end of the day it's UK, Gibraltar, NI that suffers most, short term damage to some Irish industries and nothing more than a blip for rest of EU.