The duo come into the Queensland squad to prepare for the clash with ladder-leaders Victoria at Junction Oval in Melbourne.
McSweeney, who made his Shield debut for Queensland at the start of the season, has been in strong form for Norths in the Queensland Premier Grade cricket competition as well as for the Queensland Academy of Sport 2nd XI in recent months.
The Australian Under-19 allrounder took a five-wicket haul with his off-breaks in the Futures League T20 series last month, the haul coming in the same week he claimed a hat-trick for Norths on the way to an eight-wicket bag.
Gannon has made a successful return after having major shoulder surgery at the end of last summer and is in line to play his first Shield match in more than 12 months.
The tall paceman has taken 30 wickets at 14.97 since resuming bowling and scored an unbeaten century for Norths recently.
He returned hauls of 6-50 and 2-12 for the QAS during the week as they moved into second spot on the Futures League 2nd XI ladder with a defeat of South Australia.
With four matches to be played in second half of the JLT Shield competition, Queensland sit third on the Shield ladder, two points behind NSW and with Victoria holding a 10-point lead.
The competition will again feature the use of the Duke ball which saw Queensland thrive last summer to host and win the Shield Final against Tasmania.
Bulls squad members will be in action for their Premier Grade clubs over the weekend for the start of the second-last round of the two-day competition.
JLT Sheffield Shield
Queensland v Victoria, Junction Oval
James Peirson (c)
(12th man to be named)
The match wil be scored live on cricket.com.au as well as live-streamed for free on the website and Cricket Live Ap.