Place two sticks (or pipes) on either side of the plant in a 60 - 45 degree angle to the ground.
Lace twine into a net/ mesh like structure between the sticks using twine, cloth, pantyhose, etc.
Lean the offending branches against the net/ mesh.
The sticks and mesh will help to support the heavy branches until the fruit matures.
Thanks, got one tomato frame in place on the worst plant - the other (Big Beef) may already be too large to force it into there. It’s actually 3 plants I think with about 11 tomatoes including the small new one on it.
It’s in a big clay pot so it’s very hard to stake the thing but thanks for the advice regardless.