I would just like to say although it is not entirely wrong to use "offer"
You would not normally "offer a plan" - You "suggest a plan"
You don't often use 'offer' in the same way as you use 'suggest'
For example :
You can OFFER a SUGGESTION. (both words can be used in one sentence here - that's how different they are)
To offer is simply to give. (or try to give - it can be rejected)
I can offer you tea, or a lift home, or yes, sometimes offer a plan or idea,
But usually when offering an 'idea' -
You would simply use the term "Suggest".
As 'Suggestion' translates basically to "plan or idea"
so in a way it's a bit silly to say you will offer someone an idea (plan)
When there is already a whole english word that says that.
However, while using 'offer' was not precisely incorrect, just uncommon,
your grammar overall was a bit flawed.
Corrections below:
1. a) *I offered you my plan. (This is slightly incorrect as it translates more like you gave away your idea instead of shared it?)
b) *I offered you to consider my plan. (This would never be used)
c) *I offered myself a great plan. (Also very wrong)
d) I offered my plan to you. (This is about as correct as the first one, but none of these sentences would ever really be used by a native english speaker)
Now these made more sense - but still had issues
2. a) I suggested you my plan. - should rather be "I suggested my plan to you." (We never use "I suggested to you, my plan". This is incorrect)
b) I suggested you to consider my plan. - "I suggested that you consider my plan"
c) I suggested myself a great plan. (This is completely wrong, perhaps you meant "A great plan was suggested by myself. Otherwise don't use 'myself' in that sentence form.)
d) I suggested my plan to you. (this one can work fine)
