>>213300530
>>213300586
The source was Manny Coto and Brannon Braga with the idea to make him an advisor.
Not sure how the hell that was going to work on permanent basis though unless they really were going to do a season where the NX-01 was in drydock getting the refit and they go on an Alpha Quadrant pub crawl. About only way I can think they could have made it work is if they made Shran a liaison to Starfleet so they had an excuse to bring him along occasionally but not overstay his welcome.