Pierre Teilhard de Chardin was a French philosopher and Jesuit Catholic priest who was mentioned in the Royal Wedding of Prince Harry and Meghan Markle.
Dangerous Tendencies of Cosmic Theology: The Untold Legacy of Teilhard De Chardin was a 2017 journal article in which author John Slattery claims:
from the 1920s until his death in 1955, Teilhard de Chardin unequivocally supported racist eugenic practices
Slattery repeats similar claims in his 2018 essay, Pierre Teilhard de Chardin's Legacy of Eugenics and Racism Can't Be Ignored.
Racial Eugenics in Liberal-Progressive Christian Theology: Cosmic Evolution, is a blog article by J.R. Miller (2020) that leans on Slattery's research to make similar claims.
The sources provide supposed quotes to support their arguments. A cursory search of Teilhard's alleged quotes tend to lead back to references to the same articles, and not the source material.
Do the yellows—[the Chinese]—have the same human value as the whites? [Fr.] Licent and many missionaries say that their present inferiority is due to their long history of Paganism. I'm afraid that this is only a 'declaration of pastors.' Instead, the cause seems to be the natural racial foundation... Christian love overcomes all inequalities, but it does not deny them.
We must recognize... the vital importance of a collective quest of discovery and invention no longer inspired solely by a vague delight in knowledge and power, but by the duty and the clearly-defined hope of gaining control (and so making use) of the fundamental driving forces of evolution. And with this, the urgent need for a generalized eugenics (racial no less than individual) directed, beyond all concern with economic or nutritional problems, towards a biological maturing of the human type and of the biosphere.
My provisional conclusion: the supposed quotes are a mix of total fabrications and quote mining.
EDIT: Trashing Teilhard is a reply to Dangerous Tendencies of Cosmic Theology. Quote:
Slattery doesn’t deny that the bulk of Teilhard’s religious writings are uncontroversially Christian and in tune with Catholic teaching. Yet he ignores this fact in defining what he calls Teilhard’s “legacy.” Though he surely knows that most readers will be unfamiliar with the man and his thought, he has decided to expose them first to what he considers Teilhard’s most sinister side. In the process he takes a thimbleful of quotes out of context, posts them on a blank background, and says nothing substantive about the remaining 99.9 percent of Teilhard’s work. Failing to take into account the general architecture of Teilhard’s thought always leads to the kinds of exaggeration and distortion that Slattery commits.