Before we start - this is assuming she survived the Androids, which is quite possible in my opinion as her palace is out in the middle of a desert.
Also, we've got no information regarding what happened to her as - like with Future Master Roshi - we hear nothing about if she's dead or not.
(Be aware - there's going to be a lot of text).
Assuming Fortuneteller Baba survived, she probably could have saved Future Trunks' timeline herself. If Future Bulma gave her the money she wanted (10 million zeni) or a gift (like she asked from Goku for bringing Frieza back), I think she could get rid of the Androids using one or two of the following methods.
For argument's sake, we'll set this in Age 780 before Future Gohan and Future Trunks start training together.
01. Using Spike the Devil Man: Spike might not be very powerful compared to the Z-Fighters, but his "ace in the hole" is his Devilmite Beam; a one-shot-kill attack that "transforms an opponent's own negative thoughts into destructive beams that can annihilate anything in their path".
In the game Budokai Tenkaichi 3 as part of one of the "What-if?" ideas, Spike appeared instead of Goku/Future Trunks and was able to use this attack to kill Mecha-Frieza, King Cold and their soldiers. Also, considering what Future Android 17 and Future Android 18 get up to, I'd say they have plenty of negative thoughts that could be exploited.
As such, and possibly with Fangs the Vampire and See-Through The Invisible Man providing distractions (the Androids unable to sense Energy), Spike should be able to blast both Androids with his Devilmite Beam - destroying them both.
02. Reviving Goku using the 24-Hour Revival (Version 01) - This would be similar to what she did at the end of the Great Saiyaman Saga. Since Future Goku is dead, there's no need to worry about the Heart Virus.
Furthermore, since Goku died in Age 766, this would give him around 14 years of time training in the Other World - like what happened after Goku was killed in the Cell Games Saga - and thus plenty of time to grow stronger; improving his regular Super Saiyan form and possibly discovering Super Saiyan 2 and Super Saiyan 3. With all this, he should easily be able to dominate the Androids and destroy them both.
On a side note, I'd love to see the look on their faces if Goku did power up to SSJ3 (just to show off for his "last battle on Earth") - similar to this: https://www.youtube.com/watch?v=-dY2IBPzJhI
03. Reviving Goku using the 24-Hour Revival (Version 02) - This time when Fortuneteller Baba brings Goku back, Goku reunites with Gohan and - since Gohan and Trunks are the future of Earth's protection as Goku can't be brought back with the Dragon Balls - decides to teach him an ability that he learned in the Other World; Metamoran Fusion.
After teaching him this and successfully performing it, the two confront the Androids together as Gokhan. This fusion should be more than capable of turning 17 and 18 into scrap; just imagine it with this music playing in the background: https://www.youtube.com/watch?v=qO-ywIx6wC4
The upside of bringing back Goku as well means the following:
With King Kai's help, Goku could use instant transmission to take himself and Gohan to Yardrat and New Namek; Gohan getting the co-ordinates of both worlds for later.
On New Namek - and depending if their dragon balls have been "upgraded" or not, their Dragon Balls could be used to bring back Piccolo (along with the other Z-Fighters and their allies). This means Kami is revived, Earth's Dragon Balls are reset, Trunks gets his dad back, Dende may take over as Earth's Guardian and Korin is brought back and able to start regrowing Senzu beans.
If the Namekian Dragon Balls haven't been upgraded, Earth Dragon Balls could be used to revive everyone else killed by the Androids in the past year.
Learning Yardrat's location (and with the Heart Medicine around in case it's needed), the Z-Fighters could train there to grow stronger and all learn Instant Transmission along with the other abilities like Cloning, Gigantification, Healing, etc.
Goku and Kami could also inform the group about the Hyperbolic Time Chamber, so they can get stronger that way as well.
With Goku teaching Gohan Metamoran Fusion, this means Gohan and Trunks have the option of becoming Gohanks when necessary.
Goku would get a chance to give Chi-Chi a proper goodbye.
There's more people around to deal with Future Cell, Future Babidi and Future Dabura - meaning Shin and Kibito might not die and Majin Buu will remain sealed away.
Curious to see what you guys think about all this.
