have one´s work cut out

[beachboy]

I´ll have my work cut out for me to learn Spanish
I´ll have my work cut out for me learning Spanish

Any difference between the above sentences?

In terms of conceptual meaning, would "I´ll have to struggle hard to learn Spanish" convey the same?

 

[Horsa]

Both are in use and I don't feel a big difference in meaning - to learn is probably slightly more formal.

Yes you are right with the meaning

 

[apex2000]

I´ll have my work cut out for me to learn Spanish
I´ll have my work cut out for me learning Spanish

Any difference between the above sentences?

In terms of conceptual meaning, would "I´ll have to struggle hard to learn Spanish" convey the same?

Your last sentence is fine; it makes it clear.
For the first two the following also gives the same impression:

I'll have my work cut out to learn Spanish.
..................................learning............

The 'for me' is unnecessary and incorrect simply because you are the one speaking and there is no need to repeat that. Alternatively you could also say:
For me, it will be hard to learn Spanish.