New Sprites Found
On August 30th, 2019, dataminer @Chrales tweeted a post revealing the discovered sprites for Unova Pokemon arriving in Pokemon GO.
Only a portion of the generation's sprites have been discovered by Chrales, but it does give some insight into what Pokemon might be releasing first.
recently found unova pokémon pic.twitter.com/oQpjVUg8yc
— Chrales (@Chrales) August 30, 2019
The revealed Pokemon in the datamine are:
Snivy

Servine

Serperior

Tepig

Pignite

Emboar

Oshawott

Dewott

Samurott

Patrat

Watchog

Lillipup

Herdier

Stoutland

Purrloin

Liepard

Pansage

Simisage

Pansear

Simisear

Panpour

Simipour

Munna

Musharna

Pidove

Tranquill

Unfezant

Blitzle

Zebstrika

Woobat

Swoobat

Drilbur

Excadrill

Audino

Timburr

Conkeldurr

Dwebble

Scraggy

Scrafty

Yamask

Cofagrigus

Foongus

Amoonguss

Ferroseed

Ferrothorn

Klink

Klang

Klinklang

Litwick

Lampent

Chandelure

Golett

Golurk

Heatmor

Durant

Deino

Zweilous

Hydreigon

Cobalion

Virizion

Terrakion

We do not have any more details on the moves these Pokemon will have, that information is chosen by Niantic. The Pokemon's stats are available to view on their respective pages.
Little is known about the methods Chrales uses to gain this information, but he does typically showcase his findings on his Twitch channel after an announcement.
Check out our list below for our Gen 5 recommendations.