BigQuery select __TABLES__ from all tables within project?

Using BigQuery, is there a way I can select __TABLES__ from every dataset within my project? I've tried SELECT * FROM '*.__TABLES' but that is not allowed within BigQuery. Any help would be great, thanks!

__TABLES__ syntax is supported only for specific dataset and does not work across datasets

What you can do is something as below

#standardSQL
WITH ALL__TABLES__ AS (
  SELECT * FROM `bigquery-public-data.1000_genomes.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.baseball.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.bls.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.census_bureau_usa.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.cloud_storage_geo_index.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.cms_codes.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.common_us.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.fec.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.genomics_cannabis.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.ghcn_d.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.ghcn_m.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.github_repos.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.hacker_news.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.irs_990.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.medicare.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.new_york.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.nlm_rxnorm.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.noaa_gsod.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.open_images.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.samples.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.san_francisco.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.stackoverflow.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.usa_names.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.utility_us.__TABLES__` 
)
SELECT *
FROM ALL__TABLES__

In this case you need to know in advance list of datasets, which you can easily do via Datasets: list API or using respective bq ls

Please note: above approach will work only for datasets with data in same location. If you have datasets with data in different locations you will need to query them in two different queries

For example:

#standardSQL
WITH ALL_EU__TABLES__ AS (
  SELECT * FROM `bigquery-public-data.common_eu.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.utility_eu.__TABLES__` 
)
SELECT *
FROM ALL_EU__TABLES__