A more creative upgrade on Sissoko could do a lot for us without changing our first eleven.
Another option is, like against Real, Liverpool and United, to play Winks as the deepest midfielder instead of Dier/Wanyama. Essentially adding another more creative midfielder to our line up. Dropping Dier, and to a lesser extent Wanyama, will perhaps be difficult for Pochettino though.
Of our four "natural" deep midfielders Winks is the only truly creative player in my opinion. Another creative option here, either through a transfer or perhaps bringing through Onomah would increase our creative options. Though replacing Wanyama or Dembele short term would be both unpopular with many fans and unlikely from Pochettino. Dier is untouchable imo.