Godly Gift is one of my favorite OMs, and with it being Leader's Choice this month, I wanted to get the conversation started with some mons to use or be aware of if you're new to the tier and don't know where to start. This will by no means be exhaustive, there are lots of good Gods and Receivers I won't mention here, but it's a place to start.
Gods
There are two things to consider when selecting a God for Godly Gift. First, it will be part of your team, and the only Uber you are allowed, so selecting a mon that contributes to winning in its own right is important. Second, it will be donating its stats and quite literally shape your whole teambuilding process. As a result, Ubers like Cinderace or Marshadow that are mostly Uber for their abilities, moves, and/or typings generally make poor Gods. Great Gods are both good mons and have great stats to donate.
Eternatus is probably the best example of a God that is both an amazing mon and donor. It has amazing offenses, typing, and movepool, allowing it to run a variety of sets, from Specs to Stall Breaker to Cosmic Power Sweeper and everything in between. Additionally, it's 140 HP, 145 SpA, and 130 Spe make it a fantastic donor that super-charges your offense without totally leaving your defenses out to dry. It's 95/95 defenses are nothing to write home about, but can usually at least give your defensive mons a boost to your off stats. It is arguably the best God in the meta right now, and a great place to start teambuilding, or a threat to prepare for.
Kyogre is another threat to be prepared for. It survived a suspect test last time Godly Gift had a ladder, and is a great example of a God that is fantastic as a stand-alone mon. Everyone knows by now how powerful Kyogre's attacks are in rain, and in a meta where at least half of the team has standard OU defenses and three of the best special water switchins (Blissey, Chansey, and Toxapex) are banned, it's a potent force. It can still donate it's 150 SpA and 140 SpD, but the rest of its stats are more middling, making it a little less splashable than Eternatus.
Calyrex-Ice is an interesting God, offering 165 Atk, 150 Def, and 130 SpD to its receivers. What makes it especially interesting is it's stats are almost tailor-made for Trick Room, which it also has access to, turning it's worst stat (speed) into a viable donor stat. Trick room is arguably more viable in Godly Gift than a lot of other metas, largely thanks to this guy.
And if all you care about is offenses, these are the Gods for you. Offering 120/170 offenses and okay 95 speed, these are your guys for putting a walloping on the other team. They're also great Gods for speed-boosting team archetypes like Rain, where dealing damage fast is the name of the game.
Receivers
One of my favorite things about Godly Gift is the huge range of creativity it allows in its receivers. Tons of mons in UU, RU, and even NU have good typings/abilities/movepools, but lack the stats to really take advantage of them. In Godly Gift, we can fix that. I would strongly encourage anyone playing this tier to find unique receivers that otherwise would not see use, and see what they can do. Is Copperajah good if you give it 130 speed? I have no idea, but here, you can find out. That being said, there are obviously some receivers that stand out and you need to be prepared for if you want to be competitive.
Marowak-A is probably the premier speed receiver in Godly Gift and an absolute terror to face. It's attack, boosted by Thick Club, is equivalent to a fully-EVed 210 Attack stat, and it has two high-powered STABs with fantastic coverage between them. Give it 130+ base speed, and it's the most threatening offensive sweeper in the tier. It can further boost its attack with Swords Dance and is immune to Normal (more on why that's important later). While speed is the easiest thing to receive, if you're running Trick Room (or just really, really hate stall), putting it in the attack slot gives it unimaginable and unwallable power.
Dragapult is very similar to Maro, except instead of having amazing attack and lackluster speed, it has amazing speed and lackluster attack. However, if you give it 150+ Special Attack (or Attack, but it's special movepool is better) there is nothing lackluster about it anymore. Ghost STAB has fantastic coverage and it has the movepool to hit almost anything it wants. U-Turn also allows it to be a great offensive pivot and punish the opponent even when they have a reliable switchin by gaining momentum.
Meet Godly Gift's premier revenge killer
no, seriously and the reason Ghost typing is so valuable on offensive mons. With Light Ball doubling its attack and access to Fake Out + Extremespeed, Pikachu is by far the strongest priority user in the tier. It also has Knock Off to knock out those pesky ghosts that are always trying to switch in and Volt Tackle to KO almost any non-ground type, as long as you don't mind getting KOed yourself from recoil.
Unaware is an amazing ability that is relegated to pokemon with overall sub-par stats. Not anymore. If your team relies on set-up moves to break through and win, you need to have a backup plan to handle these things. With Unaware, reliable recovery, and now-amazing defenses, these are no joke to break through.
TL;DR
Godly Gift is an amazing tier that rewards creative teambuilding and gives rarely used mons the tools to shine. This is far, far from an exhausting list of good Gods and receivers. There are dozens of ways to make a great team, almost certainly including undiscovered ways, and I strongly encourage anyone to go digging for receivers that have the tools to be great, but not the stats. Pick a God, fill in receivers around it, and have fun!