you need to evolve umbreon and golem, unless you wanna try catching an alpha golem on coronet highlands. Evolve Umbreon by leveling it up, making sure to change the time to nightfall and not have a fairy type move. You can get evolution items at the trading post with merit points in case you didn't know, no need to trade just use the items on the pokemon.
No 55 is pichu, can be found at Floaro gardens and nature's pantry in the Obsidian Fieldlands and at golden lowlands in the Crimson Mirelands. Its a rare spawn so you'll need to reset the area to try and get it.
No 66 and 67 is cherubi and cherrim, you'll need to harvest the shaking trees in either the heartwood in obsidian fieldlands, gapejaw bog in the Crimson Mirelands, Lonely Spring, Fabled Spring and primeval grotto in the Coronet Highlands.
Happiny's location is posted a few pages back, I don't have it so don't know it at hand. I know bonsly is a rare spawn but don't know where to find it.
No 130-132 is the Turtwig line, you can find turtwig and grottle at the bottom right of the Crimson Mirelands at the lake to the right of Ursa's Ring on the map. It is a small area and I've only ever seen 2 pokemon spawn there at a time. At least 1 turtwig is there everytime I checked but don't know if it is guaranteed.
No 134-135 is the porygon line, you can find them in time rifts at the Crimson Mirelands, not sure if they can be found in time rifts at other areas though.
Evolve haunter, there might be an alpha somewhere but I don't know where it is.
you need to collect all the wisps from each area to unlock spiritomb from what the other posts have said. I haven't done that yet and cannot elaborate any further.
Remoraid can be found in the water at Cobalt Coastlands, pretty small and camouflaged but aggressive so you'll know they are around if there's suddenly an alert symbol when you don't see anything.
Again, evolve Machoke. unless there's an alpha somewhere that I don't know of.
Same as Machamp but with magmar.
for Magnezone, you can try catching one flying around at Coronet highlands.
Not sure on how to evolve probopass, though there is an alpha if I'm not mistaken, though I don't remember where it was.
No 194 is rotom, can be found at Stonetooth Rows and sacred plaza in the coronet Highlands. It's probably somewhat rare as I've only ever see one whenever I pass through it. Can also spawn as an alpha.
There's a previous post on 199 and 200, being clefa and clefairy.
How did you get weavile? I haven't seen a normal sneasel. Sneasler evolves with razor claw as well just during the day instead of the night.
Don't know what 208 and 209 are either, sorry.
214 is mamoswine, there's an alpha at avalugg's legacy
I don't know where to get riolu unfortunately. As well as the other two which are probably legendary or mythical pokemon as my dex ends with Palkia. haven't done the postgame yet, want to complete everything else first. The last two might have been mentioned previously in the thread.
Hope this helps.