Your query doesn't make much sense. You each get the annual exemption of €1,270 but this cannot be carried over to the following year.
By merely transferring the shares between you and your wife you are essentially achieving nothing - unless the shares are eventually sold. If you were to sell shares and make a gain of more than €1,270 then it would make sense to transfer shares to your wife, who would take on the original base cost.
For example:
You want to sell shares in Company A. You bought them for 1,000 and you can sell them for 9,000 (ignore indexation). Without any transfer the gain would be as follows:
9,000 - 1,000 = 8,000
8,000 - 1,270 = 6,730
6,730 @ 20% = 1,346.
By transferring half of the shares to your wife:
Your CGT:
4,500 - 500 = 4,000
4,000 - 1,270 = 2,730
2,730 @ 20% = 546
Your wifes CGT is the same (i.e. 546). Your total CGT is 1,092 (which is 254 (i.e. 1,270 @20%) cheaper than the original amount of 1,346.
You are saving €254 and have no stamp duty (of 1%) on transfers between spouses. To arrange the transfer of ownership it may cost more than €254 so this is something that needs to be considered.