Travel from HKIA to China

Can a Chinese citizen travelling on a Chinese passport use the Shekou ferry to HKIA with a confirmed flight on China Eastern for travel from HK to Lijiang and then back to HK with further return flights HK to Xi'an. Then return back to Shenzhen on the same ferry. She is trying to avoid the need for a HK visa. These flights are about 1/2 the cost compared to SZ