Hello Philip...Welcome..
It is a bit of a challenge to give more detail advice without seeing photos, drawing or blueprint cross sectional elevations of what there is or is planned.
In general, in traditional timber frames that sit on stone plinth/socle or a full stone wall most just "rest" on these foundations by their sheer mass/weight. The better one may have some "keyin" carved into the stone, or what are called "drift pins" (usually of bronze, copper, or harder stone.) Iron became common later on but is very susceptible to "rust jacking" which will split stone and these steel drift pins or "tie downs" as they are now configured usually are of galvanized metals or protected in some fashion from oxidation (aka rust jacking.)
Stone species (type) is also part of this as the softer sand and limestones may need more of them in area with strong "weather events" that generate uplift on large overhangs.
Basically, it will most likely be some type of "drilled in" bolt type (but none full expansion bolt types as these can split stones of some variety and wall configuration) and then a structural epoxy will secure them into place. Stainless steel insert sleeves are also part of this group and then the stainless steel threaded rod is attached through the sill plate. Stainless steel shear plate attachments are also popular, and the last is a concrete "bond beam" with "J Bolts" and sill configured as part of the form work and assembly. I care not for most "bond beam" formats because of the concrete use and prefer a geopolymer as it is stronger.)
Hope that is of some service at the point...
Regards,
j
