Pathfinder variant multiclassing guidelines conversion

[Gobliin]

Is there a guide to help create new path for the variant multiclassing from pathfinder unchained?

I would like to convert some 3pp class ( like the pactmaker from the lost grimoire or the hedgewitch from sphere of power)

[Eldonauran]

Not that I am aware of. Many of the VMC options are basically useless (like gunslinger) or weak (like fighter) and range from decent (cleric) to superior (like barbarian and wizard).

If I had to design new ones (and I have home brewed a few), I usually give the stronger abilities of the class at a reduced (but scaling) level and some of the flavorful, but not quite so powerful, abilities at a delayed level but acting at full character level. If there exists a feat that mimic a class feature (like the gunslinger), I make sure that the feat that is getting replaced at that level is BETTER than just taking the feat that mimics the ability.

[digiman619]

Well, the major problem with a Hedwitch VMC is that without also giving you spherecasting, it's quite limited. How about:

Hedgewitch VMC
3rd: Choose a tradition: You get the tradition's benefit and count as having the chosen tradition for qualifying for secrets as though he possessed the appropriate Amateur secret.
7th: You gain the tradition power of your chosen tradition of a hedgewithc your level -4
11th: Choose a secret; your effective Hedgewitch level for choosing secrets is your character level -6
15th: Choose a second secret
19th: Choose a third secret.

Admittedly, you might get into trouble using Spiritualism to essentially MF your way into a sphere without spherecasting, but whatever. As for a Pactmaker:

Pactmaker VMC
3rd: Choose a constellation. You may bind one 1st level spirit from the chosen constellation. You cannot bind any other spirit except through this ability, even you complete their knowledge tasks. Your effective binder level is half your character level.
7th: Choose a secret; your effective binder level is your character level -6.
11th: You may now bind spirits of up to second level, but only ones in your chosen constellation.
15th: Choose a second secret.
19th: You may now bind spirits of up to third level, though only ones from your chosen constellation.

[Gobliin]

Thanks for your idea.

Digiman, I'm not sure about your binder version (it might be a personnal taste only) but I think your might be on the right track for the hedgewitch. I would had that you can never gain other hedgewitch tradition ( even throught secret). Also, I would change the level 15 secret to a ability that remove the -4 penalty to the power, like they do with the druid animal companion and the channel energy from the cleric. Or I would reduce it to -2.

[digiman619]

Well, a lot of the Pactmaking archetypes have the Tunneled Lore class feature that limit them to one constelation (Occult Exploiter, Totemic Sage, Soul Muse, Soul Screamer), so limiting it to one constellation seemed acceptable.

[Gobliin]

The tunnel lore also allowed starless spirit