The following is my interpretation of how Wild Shape statistics work per the PHB, based on a number of discussion sites I've found (links below) as well as how the Wild Shape Creatures tab works on D&D Beyond.
The PHB says of Wild Shape: "Your game statistics are replaced by the statistics of the beast, but you retain your alignment, personality, and Intelligence, Wisdom, and Charisma scores. You also retain all of your skill and saving throw proficiencies, in addition to gaining those of the creature. If the creature has the same proficiency as you and the bonus in its stat block is higher than yours, use the creature's bonus instead of yours."
Note 1: the description above is careful not to refer to the beast's proficiency
bonus, since that's not a stat that's published in any beast (or monster's) stat block. It does exist, since it's baked into many of its other stats, but it's not called out explicitly in the monster entry. It seems like the designers did this intentionally so that players and DMs don't have to worry about it in play - the only time you really need to refer to it is when you're creating a monster from scratch.
Note 2: the description above does NOT say you gain any of the weapon/armor/tools proficiencies of the beast (if any) while Wild Shaped - the druid only gains the beast's skill and saving throw proficiencies.
To illustrate, let's take a Level 20 Moon Druid (with some odd stats to illustrate edge cases) who has proficiency in Animal Handling, Athletics, Nature, Perception, and Survival. If they Wild Shape into a Polar Bear, their stats would look like this:
Str 20 (+5) Dex 10 Con 16 (+3) (all from polar bear's stat block)
Int 10 Wis 3 (-4) Cha 11 (all from druid's character sheet)
Saving Throws: Str +5 Dex +0 Con +3 Int* +6, Wis* +2, Cha +0 (*Int and Wis get the druid's +6 proficiency bonus for level 20, since the druid is proficient in these saves)
Skills: Animal Handling +2, Nature +8, Survival +7 (from the druid's character sheet, since these skills are based on the mental traits retained in Wild Shape form)
Athletics +11 (this is different from the druid's character sheet, since we have to replace the druid's strength with the beast's, then add the druid's proficiency bonus)
Perception +3, Passive Perception 13 (the druid normally gets a +2 to perception, but since the bear's bonus to this skill is +3 this invokes the last sentence of the quote above and we use the bonus from the bear's stat block. If the druid didn't already have proficiency in Perception they would gain it via Wild Shape, but the bonus would then only be +2 since this rule would not have been invoked.)
Attacks: Bite +7 to hit, 1d8+5 piercing; Claws +7 to hit, 2d6+5 slashing (these are taken directly from the bear's stat block - druid does NOT gain proficiency in Bite or Claw attacks since they are not skills or saving throws, so the druid's proficiency bonus is not used & we default to using the beast's stats here).
References:
https://ddb.ac/characters/27954485/XTwUro (click on Extras, then select the Polar Bear)
https://dnd.wizards.com/articl...ent-enhanced-edition
https://www.dndbeyond.com/foru...ging-wildshape-stats
https://dndbeyond.zendesk.com/...0013089534-Creatures-
https://twitter.com/JeremyECra...s/960225632578764800
https://twitter.com/calebrus44...s/557824116901023746
https://media.wizards.com/2020...ds/SA-Compendium.pdf, first question in the Ability Checks section points out attack rolls, saving throws, and attacks are all different things
This message was last edited by the GM at 20:36, Sun 03 May 2020.