Im currently shooting full frame Canon 5d Mk2 and do mostly landscapes.
Photos shown are what im looking for examples off from M43 cameras. Are these prints possible and with great detail or would I be shooting myself in the foot trying to achieve this?
I Wouldn't worry at all, the 5Dm2 was a 21mp camera, when I compared the 6D to the EM5 there wasn't a huge amount of difference in detail (I was shooting for a client off a tripod). So the newest 20mp sensors will have better colour and DR than the 5Dm2 and when using equivalent settings should be significantly better than that older camera.
So if you are happy with those results then you should be very happy with these.
It is always very difficult to judge print quality online, I took these pictures to show this forum how far 16mp goes, here is the full shot showing the crop of 16mp I used

As you can see I am using a tiny proportion of the full 16 mp, so I might be printing from about 8mp of detail

This is what 100% of that detail looks like
[ATTACH alt="here is about an 11" x 19" print from that crop hung in the studio"]2106478[/ATTACH]
here is about an 11" x 19" print from that crop hung in the studio

Here is a close up of the print. You can see focus is slightly high on the ruler so better to look at her far eye for detail. YOu can see we are actually losing more detail from the professional inkjet (produced by a fine art printer in the area on Epson premium luster paper). I hope this shows you how much quality is available.