I'd find it pretty unlikely that Silvally-Normal would drop to PU. Something to keep in mind is that Silvally-Normal's Explosion is the strongest non-ate Explosion in the game. With Normalium Z, that means it can hit with a 200BP STAB followed by a 250BP STAB, which can be boosted with Swords Dance. I've tested quite a bit in OU and even there that thing can smash holes in teams easily, and usually at worst forced a trade. It's movepool is enough to work with the nuke 'n boom strategy, with Iron Head, Crunch and Fire coverage targeting its resists. Magnet Pull and Pursuit also gives it team options to eliminate Steels and Ghosts, making it easier to smash open the opposing team.
Alongside Eeveelutions, there's also this:
220 BP Stored Power + Adaptability Hyper Voice at a potential 458 speed is brutal and the +2/+2 defense boosts give Eevee actual bulk. HP Ground covers most of the limited Normal/Psychic resists (mostly just Steel-types by PU). To give an example of its power, Eevee's Timid Stored Power hits a bit harder than Glaceon's Modest Specs Ice Beam against a neutral target. Even though it has to have Last Resort on its moveset to use Extreme Evoboost and needs to find an opening to set up, this thing has all the coverage it needs in 3 moves.
Alongside Eeveelutions, there's also this:
220 BP Stored Power + Adaptability Hyper Voice at a potential 458 speed is brutal and the +2/+2 defense boosts give Eevee actual bulk. HP Ground covers most of the limited Normal/Psychic resists (mostly just Steel-types by PU). To give an example of its power, Eevee's Timid Stored Power hits a bit harder than Glaceon's Modest Specs Ice Beam against a neutral target. Even though it has to have Last Resort on its moveset to use Extreme Evoboost and needs to find an opening to set up, this thing has all the coverage it needs in 3 moves.
+2 252 SpA Eevee Stored Power (220 BP) vs. 0 HP / 4 SpD Stoutland: 274-323 (88.1 - 103.8%) -- 25% chance to OHKO
+2 252 SpA Eevee Stored Power (220 BP) vs. 0 HP / 0 SpD Rotom-Frost: 238-281 (98.7 - 116.5%) -- 93.8% chance to OHKO
+2 252 SpA Eevee Stored Power (220 BP) vs. 252 HP / 4 SpD Assault Vest Muk: 336-396 (81.1 - 95.6%) -- 56.3% chance to OHKO after Stealth Rock
+2 252 SpA Eevee Stored Power (220 BP) vs. 252 HP / 252+ SpD Eviolite Clefairy: 158-187 (45.9 - 54.3%) -- 53.5% chance to 2HKO
+2 252 SpA Adaptability Eevee Hyper Voice vs. 80 HP / 0 SpD Grumpig: 192-226 (59.8 - 70.4%) -- guaranteed 2HKO
+2 252 SpA Eevee Hidden Power Ground vs. 0 HP / 0 SpD Mawile: 224-264 (92.9 - 109.5%) -- 56.3% chance to OHKO
+2 252 SpA Eevee Hidden Power Ground vs. 172 HP / 0 SpD Probopass: 196-232 (64.4 - 76.3%) -- guaranteed 2HKO after Leftovers recovery
+2 252 SpA Eevee Hidden Power Ground vs. 252 HP / 0 SpD Eviolite Metang: 112-132 (34.5 - 40.7%) -- guaranteed 3HKO
252+ Atk Choice Band Stoutland Return vs. +2 0 HP / 0 Def Eevee: 211-250 (84 - 99.6%) -- guaranteed 2HKO
252+ Atk Iron Fist Monferno Mach Punch vs. +2 0 HP / 0 Def Eevee: 108-128 (43 - 50.9%) -- 3.5% chance to 2HKO
+2 252 SpA Eevee Stored Power (220 BP) vs. 0 HP / 0 SpD Rotom-Frost: 238-281 (98.7 - 116.5%) -- 93.8% chance to OHKO
+2 252 SpA Eevee Stored Power (220 BP) vs. 252 HP / 4 SpD Assault Vest Muk: 336-396 (81.1 - 95.6%) -- 56.3% chance to OHKO after Stealth Rock
+2 252 SpA Eevee Stored Power (220 BP) vs. 252 HP / 252+ SpD Eviolite Clefairy: 158-187 (45.9 - 54.3%) -- 53.5% chance to 2HKO
+2 252 SpA Adaptability Eevee Hyper Voice vs. 80 HP / 0 SpD Grumpig: 192-226 (59.8 - 70.4%) -- guaranteed 2HKO
+2 252 SpA Eevee Hidden Power Ground vs. 0 HP / 0 SpD Mawile: 224-264 (92.9 - 109.5%) -- 56.3% chance to OHKO
+2 252 SpA Eevee Hidden Power Ground vs. 172 HP / 0 SpD Probopass: 196-232 (64.4 - 76.3%) -- guaranteed 2HKO after Leftovers recovery
+2 252 SpA Eevee Hidden Power Ground vs. 252 HP / 0 SpD Eviolite Metang: 112-132 (34.5 - 40.7%) -- guaranteed 3HKO
252+ Atk Choice Band Stoutland Return vs. +2 0 HP / 0 Def Eevee: 211-250 (84 - 99.6%) -- guaranteed 2HKO
252+ Atk Iron Fist Monferno Mach Punch vs. +2 0 HP / 0 Def Eevee: 108-128 (43 - 50.9%) -- 3.5% chance to 2HKO