INON INC. confirmed that INON accessories usable/designed for GoPro HERO9 are usable for HERO10 as well. Since HERO10 optics is identical to HERO9, performance of INON attachment lenses (field of view, minimum focus distance) is same. Variety of INON adapters, tray, arms, tripod are ready to use via SD Front Mask for HERO9/M67 Filter Adapter for HERO9.
[Combination example of INON accessories and HERO10]
Left, center left: SD Front Mask for HERO9 on HERO10
Center right: UFL-G140 SD semi-fisheye lens on HERO10
Right: UCL-G165 SD wide close-up lens on HERO10
You can find more detail of INON accessories for GoPro cameras here: http://www.inon.jp/products/gopro/hero/sdfrontmaskhero9.html