Help matching blackwood wood finish

Hi All, first time poster but long time reader. I've been dabbling in mid century chair resto for a year or two. A while back I restored a set of 1950's Fler blackwood dining chairs but after stripping and sanding them and applying danish oil I noticed different sections came up a VERY different shade, the contrast is almost the difference between black and white in some sections. I'm sure it's not meant to look like that.

Now I'm restoring a beautiful pair of Blackwood 1960's TH Brown Swivel Stools and have stripped and sanded them but don't want to make the same mistake. There are 2 stools and the legs on each side are made of two pieces. On one chair the timbers on one side have a distinctly different colour.

I have done some research and there's talk of using stain to match, and the Americans suggest an all over "toner". (Not sure if there's a difference between stain and toner?).

I just want the colour on each side of these legs to match. I plan to danish oil both chairs once I have colour matched.

Has anyone got any suggestions on how I can do this? Will danish oil apply over stain if that's what I use? Is toner a thing? (and if so where can I buy it?). Or should I just leave it and danish oil it natural?

Thanks in advance for your help brains trust! Look forward to your responses. Pic attached for reference.