Neymar there is still no speculation regarding his departure because so far no official offer has come to PSG for Neymar. I think it will make him stay longer with PSG because he is not in a hurry to leave PSG because he has a bigger salary at PSG. Mbappe is also reportedly ready to be released by PSG if there are interested who are ready to pay the price they want. Apart from that, only Real Madrid is often associated with Mbappe and no EPL team is really serious about getting Mbappe at 250 million.
I think it's still very reasonable that no team has come to PSG to propose to Neymar, because maybe every team has also seen how Neymar performed in the previous season so that other teams are not too hasty to see Neymar as an option to be targeted. Moreover, there are still many other players that can be obtained at a price that may not be much different from Neymar and regarding rumors of Mbappe himself it is still unclear where he will go next season even though there has been news linking him to Real Madrid at this time.