From July 25th, 2021 until August 29th, 2021, the Shiraberu-kun and the Pokémon Center Pika Pika Big Investigation! (しらべる君とポケモンセンターピカピカ大調査！) will be held at Pokémon Centers nationwide! It is a collaboration project with "Let's Go Shiraberu-kun!" from the variety show Pokénchi. There are lots of fun plans, including gifts for shopping! More information will be announced on Pokénchi and on the official Pokemon website. Be sure to check it out!

Update: On August 26th, 2021, the official Japanese Pokémon website announced that there would be temporary closures of Pokémon Centers and Pokémon Stores in areas under an Emergency Declaration for COVID-19. As a result, the Shiraberu-kun and the Pokémon Center Pika Pika Big Investigation! campaign ended on August 27th, 2021 instead of August 29th, 2021.

What is Let's Go Shiraberu-kun!

I want to see! I want to ask! I want to investigate! Let's Go Shiraberu-kun! is a program segment where Abareru-kun goes out of his Pokémon home to find out all about Pokémon! The segment debuted in Pokénchi #273.

Pikachu Mask Stickers as a present!

During this period, patrons of the Pokémon Centers in Japan will receive a Pikachu mask sticker when they make a purchase at any Pokémon Center nationwide. Put it on your mask and decorate it to look like Pikachu's cheeks!

Campaign Notice:

• Only one present will be given per checkout.
• The number of gifts is limited. The campaign will end as soon as they are gone, even during the campaign period.
• Please note that the contents of the gift are subject to change.
• The gifts are not for sale.
• The image is for reference only. Please note that the actual image may differ.
• The present can be used as a regular sticker.
• The present is subject to change or cancellation without notice. Please be aware of this in advance.

Source: https://www.pokemon.co.jp/info/2021/07/210716_p02.html