According to what reporter Adrian Dater is reporting, based on what he's heard, the Flyers would possibly acquire Owen Tippett, Matthew "Mackie" Samoskevich (first round pick, 24th overall in 2021) and a draft pick.
In return, the Panthers would receive Claude Giroux. (Possibly at 50% of his salary) Dater mentions that this is unconfirmed, but it's what he's heard and is the most likely scenario at this point.
However, according to the renowned Pierre LeBrun, there is still no trade for Claude Giroux and the Colorado Avalanche GM still seems to be in the running.
Everything indicates that it will be between the Avalanche and the Panthers, but most likely the Panthers. (according to several sources, including Elliotte Friedman)
Please note that Giroux will not play Friday or Sunday with the Flyers. The team will keep him out of the game, until he is traded, by the trade deadline.