No, there is no ferry from Cork to Plymouth. Swansea would be the nearest.
no, there is a ferry from Cork to Swansea
No
No. You would have to travel to England first and get a ferry from there.
insufficient demand
no
You would need a truck and ferries. Get it to Roscoff in northern France. From there you can get a ferry direct to Cork. You could also go by various ferries from France to England and then go from Wales to Ireland, or go from northern France by ferry to Rosslare.
Sherkin Island is off the coast of Co. Cork in south-west Ireland, a ten minute ferry ride from Baltimore.
On Brittany Ferries the journey is six hours by day and eight hours by night
Zero because a ferry is a short, trip boat and would not travel that far in open sea. (Ferry times take , on average, about 20 hours- operating from Bilbao and Santander in Spain: Portsmouth an Plymouth in England. FRC)
No ferries run from Cornwall to Ireland. You'll have to go Swansea or Fishguards in Wales to get to Cork. You can sail from Penzance to the Isles of Scilly or across the River Fal on the King Harry Ferry. Leaving Cornwall is a mission!
At there closest points they are about 22 miles or 38 kilometres apart. Cork is Ireland's largest county, so there are parts of it that are a long way from Clare. To go from north Clare to south Cork could be close to 200 miles, if you go by road. A ferry across the Shannon could shorten the journey closer to 150 miles. See the map below of that area of Ireland. County Limerick is between the two counties at their closest points. You would take the ferry from Killimer in county Clare to Tarbert in county Kerry and then continue on to count Cork.
No. You could get a ferry from Dublin to Liverpool or Holyhead and drive from there. You could drive from Dublin to Larne, near Belfast, and then get a ferry to Stranraer in Scotland and drive from there, or you could just fly.