AS I mentioned in the other Thread on basically the same thing (and I'm only posting here in case folks look here before there), The mods works great. Everything from SF2e is included, except random stuff from SFS2e Scenarios. Add in the Starfinder PLaytest Mod as well. This will give you the mechanic and Technomancer. Since everything has a listed source, you can easily weed out any unwanted Pathfinder elements, or let players use them, adding even more options to your game. I run Starfinder Society games and a Pathfinder/Starfinder crossover home game on Foundry and all seems to work great.
Note one thing though, You will have to manually add any modules or Adventure paths. The races are already there, but most everything else is not. It's not much work if you have the PDFs, but copying all creature stats can be a bit time consuming.