Never happened but for years there was a rights dispute over Bond film rights, which resulted in Never Say Never Again, which remade Thunderball although with some slight changes, with Derval being changed back to Patachi and the whole body double plot (Which slowed down Thunderball's first act) changed to be Patachi like in the novel(but under duress) and the Nassau setting of both the novel and the first film mostly ditched (apart from a few scenes) for a more international setting.
This mainly focused on THUNDERBALL, but also Blofeld and SPECTRE, since the latter were both introduced in the novel version of Thunderball. (The movies introduced them a bit earlier, adding them to the plots of Dr.No and FWRL, which the novel versions simply had Russian agents/proxies).
While NSNA didn't really lead to anything there were attempts again to make a third Thunderball remake and perhaps a series of rival Bond films featuring SPECTRE and a non-Brosnan Bond.
Of course all this eventually got settled and SPECTRE returned to proper Bond in 2015, with the plots of the earlier Craig films and Quantum retconned to have been SPECTRE/Blofeld all along.
The hypothetical third Thunderball might've been called WARHEAD 2000. Reportedly Liam Neeson was approached, but they also wanted Timothy Dalton back (Dalton left during the 1989-1995 break although he did have the option to return for Goldeneye), and think there was even talk of getting Connery as the villain, perhaps Blofeld or Largo. Not only would there be a "battle of Bonds" between the two franchises but on screen as well.