You guys will be forced to become limited company directors in Ireland, will be based where they need you and will find yourselves liable to pay social security in the country where they put you, you will receive no guidelines at all about tax and social security laws in the various countries where you will be based.
You will be personally liable for any tax/SI scam since you will also be the directors of your own company.
The risk if finding yourselves with a big training loan to re-pay and the tax men chasing you.
In many EU countries tax and SI fraud is a criminal offence punishable with jail time.....be careful.