Z-Conversion Porygon-Z seems like it has a lot of potential. You get to change the STAB you're exploiting Adaptability with on top of +1 in every stat (going Ghost-type with Shadow Ball seems pretty strong, but the optimal choice will depend on what defensive teams are using) perhaps with Shadow Ball / Psyshock / HP Fighting.
It's surprisingly bulky at +1/+1 too; Jolly Tyranitar's Crunch will always fail to KO ghost-poryz if SR is not on the field (presumably it almost always will be, but this is just for illustrative purposes). Whether you run Modest or Timid will depend on how popular the base ~150s are; Modest Porygon-Z can still outrun Mega Lopunny and Mega Manectric at +1 and easily OHKOes both, so that nature seems stronger (and it clinches a lot of nice KOs on things like Gliscor while enabling the small chance of a Blissey 2HKO with Psyshock if it is a Softboiled variant).
There's no way (that I can think of) to scout what type it will be after setting up either, so it might make a reasonable lure.
It's surprisingly bulky at +1/+1 too; Jolly Tyranitar's Crunch will always fail to KO ghost-poryz if SR is not on the field (presumably it almost always will be, but this is just for illustrative purposes). Whether you run Modest or Timid will depend on how popular the base ~150s are; Modest Porygon-Z can still outrun Mega Lopunny and Mega Manectric at +1 and easily OHKOes both, so that nature seems stronger (and it clinches a lot of nice KOs on things like Gliscor while enabling the small chance of a Blissey 2HKO with Psyshock if it is a Softboiled variant).
There's no way (that I can think of) to scout what type it will be after setting up either, so it might make a reasonable lure.