Goku and Vegeta could easily overwhelm #17, but I think #18 could easily handle everyone she's against besides Trunks who would give a bit off difficulty (though she'd eventually wear him down).
If Tienshinhan and Krillin were smart enough to know that Taiyōken + Kienzan = Victory, then they won't needs Trunks and the others to win. Future 18 would wears Trunks down similar to how Present 18 did to Vegeta. Everyone besides Piccolo and Trunks gets one shotted. Goku and Vegeta come in the last moment and secure the victory.