@bwud: now i understand what you are after.
i can find only one 400mm or more tele lens for APS-C image circle ("crop sensor") for Canon EF mount (and Nikon, not Sony): Tamron 18-400/3.5-6.3 Di II VC HLD. for an extreme superzoom it gets rather positive reviews.
https://dpreview.com/samples/9152094990/gallery-impressions-tamron-18-400-f3-5-6-3
https://www.ephotozine.com/article/tamron-18-400mm-f-3-5-6-3-di-ii-vc-hld-review-31259
at the long end performance does drop quite a bit, as is to be expected.
it seems to be usable on canon Ff cameras as well (ofc with limitations).
https://www.dpreview.com/forums/thread/4203828
the lens is very compact at D 79 x L 124mm, 72 filter thread and lightweight at 705 g. current prices start at euro 555,- so it is indeed significantly less than the tamron/Sigma 150-600 versions. otoh, when these are used "in crop mode" or if image is cropped to APS-C size in post processing - angle of view on the long end would be equivalent to 960 mm vs. 640 for the tamron 18-400.