There are mechanics in game that allow for coupon "transfer", however more accurately they are some sort of loss or cut that makes the "transfer" have both pros and cons:
1. Anniversary Envelope: person who recharges can send a % of their ingots in the form of coupons to their group mates. Both limited in who gets it and %.

2. Plundering: a plunderer can get coupons by attacking and successfully winning a plunder, however it cuts the convoyer's coupons and may result in less than appreciative social situations.

3. Group summons trades: a player can put up group chakra for coupons, the purchaser has to buy with ingots. This is not a good method to get group summons chakra as you can just trade chakra and a waste of ingots.

In terms of just straight transferring coupons (or items) as gifting / trade with no cons, it's not a great idea as it can lead to illegal (in game) actions.